## UGC NET June-2019 CS Paper-2

 Question 1
How many are there to place 8 indistinguishable balls into four distinguishable bins?
 A 70 B 165 C 8​ C​ 4 D 8​ P​ 4T
Engineering-Mathematics       Combinatorics
Question 1 Explanation:
This is precisely the problem we saw to solve the r-combination with repetition:
= C(8+4-1,8)
= 11 C​ 8
= 11! / (8!(11-8)!)
= 165
 Question 2
Match List-I with List-II:
List-I                                                                          List-II
(Software process Models)                             (Software System)
(a) Waterfall model                        (i) e-business that starts with only the basic functionality and then moves on to more advanced
features.
(b) Incremental development       (ii) An inventory control system for a supermarket to be developed in a highway
(c) Prototyping                              (iii) A virtual reality system for simulating vehicle navigation in a highway.
(d) RAD                              (iv) Automate the manual system for student record maintenance in a school
Choose the correct option from those given below:
 A (a)-(ii),(b)-(iv),(c)-(i),(d)-(iii) B (a)-(i),(b)-(iii),(c)-(iv),(d)-(ii) C (a)-(iii),(b)-(ii),(c)-(iv),(d)-(i) D (a)-(iv),(b)-(i),(c)-(iii),(d)-(ii)
Software-Engineering       Software-process-models
Question 2 Explanation:
Waterfall model→ Automate the manual system for student record maintenance in a school
Incremental development→ e-business that starts with only the basic functionality and then moves on to more advanced features.
Prototyping→ A virtual reality system for simulating vehicle navigation in a highway.
RAD→ An inventory control system for a supermarket to be developed in a highway
 Question 3
A computer has six tapes drives with n processes competing for them. Each process may need two drives. What is the maximum value of n for the system to be deadlock free?
 A 5 B 4 C 3 D 6
Question 3 Explanation:
Each process needs 2 drives. So for deadlock just give each process one drive. So total 6 process can be given 1 drive each and can cause deadlock. So to break deadlock just reduce 1 process.
So maximum no. of process for the system to be deadlock free is 5.
 Question 4
In the context of 3D computer graphics, which of the following statements is/are TRUE?
P: Orthographics transformations keep parallel lines parallel
Q: Orthographic transformations are affine transformations
Select the correct answer from the options given below:
 A Both P and Q B Neither P and Q C Only P D Only Q
Computer-Organization       Graphics
 Question 5
Which of the following statements are DMl statements?
(a) Update [tablename]
Set [ columnname] = VALUE
(b) Delete [tablename]
(c) Select * from [tablename]
 A (a) and (b) B (a) and (d) C (a), (b) and (c) D (b) and (c)
Database-Management-System       SQL
Question 5 Explanation:
 Question 6
What percentage(%) of the IPv4, IP address space do all class C addresses consume?
 A 12.5% B 25% C 37.5% D 50%
Question 6 Explanation:
Total possible IP numbers numbers of all classes 0 to 255.
Class-A: 0 to 127. It means 50%
Class-B: 128 to 191. It means 25%
Class-C: 192 to 223. It means 12.5 %
Class-D: 224 to 239. It means 6.25%
Class-E: 240 to 255. It means 6.25%
 Question 7
Which of the following key constraints is required for functioning of foreign key in the context of relational database?
 A Unique key B Primary key C candidate key D Check key
Database-Management-System       Constraints
Question 7 Explanation:
Foreign key is a key whose values depends on the primary key of a relation. So for the functioning of a foreign key in the context of relational database we need a primary key.
 Question 8
Software Reuse is
 A The process of analysing software with the objective of recovering its design and specification B The process of existing software artifacts and knowledge to build new software C Concerned with reimplementing legacy system to make them more maintainable D The process of analysing software to create a representation of a higher level of abstraction and breaking software down into its parts to see how it works
Software-Engineering       Software-Reengineering
Question 8 Explanation:
Software Reuse is the process of existing software artifacts and knowledge to build new software.
 Question 9
Which of the following is principal conjunctive normal form for [(pVq) ∧ ~p → ~q]?
 A pV~q B pVq C ~p Vq D ~p V ~q
Engineering-Mathematics       Propositional-Logic
Question 9 Explanation:
 Question 10
Match List-I with List-II
List-I                          List-II
(a) p → q                (i) ¬(q → ¬p)
(b) p v q                  (ii) p ∧ ¬q
(c) p ∧ q                  (iii) ¬p → q
(d) ¬(p → q)            (iv) ¬p v q
Choose the correct option from those given below:
 A (a)-(ii);(b)-(iii);(c)-(i);(d)-(iv) B (a)-(ii);(b)-(i);(c)-(iii);(d)-(iv) C (a)-(iv);(b)-(i);(c)-(iii);(d)-(ii) D (a)-(iv);(b)-(iii);(c)-(i);(d)-(ii)
Engineering-Mathematics       Propositional-Logic
Question 10 Explanation:
 Question 11
Consider the following methods:
M​ 1 ​ : mean of maximum
M​ 2​ : Centre of area
M​ 3​ : Height method
Which of the following is/are defuzzification method(s)?
 A Only M​ 1 B Only M​ 1​ and M​ 2 C Only M​ 2​and M​ 3 D M​ 1​ , M​ 2​ and M​ 3
Engineering-Mathematics       Fuzzy-logic
Question 11 Explanation:
Defuzzication Methods: Following defuzzication methods are known to calculate crisp output → Maxima Methods
1.Height method
2.First of maxima (FoM)
3.Last of maxima (LoM)
4.Mean of maxima(MoM)
→ Centroid methods:
1. Center of gravity method (CoG)
2. Center of sum method (CoS)
3. Center of area method (CoA)
→ Weighted average method
 Question 12
Replacing the expression 4*2.14 by 8.56 is known as
 A Constant folding B Induction variable C Strength reduction D Code reduction
Compiler-Design       Code-Optimization
Question 12 Explanation:
Take variable i=4*2.14
We are simply folding the value into 8.56 because to avoid multiplication costly operation.
 Question 13
A fuzzy conjunction operator denoted as t(x,y) and fuzzy disjunction operator denoted as s(x,Y) form dual pair if they satisfy the condition:
 A t(x,y)= 1-s(x,y) B t(x,y)=s(1-x,1-y) C t(x,y)=1-s(1-x,1-y) D t(x,y)=s(1+x,1+y)
Engineering-Mathematics       Fuzzy-logic
Question 13 Explanation:
 Question 14
Which data structure is used by the compiler for managing variables and their attributes?
 A Binary tree B link list C Symbol table D Parse table
Compiler-Design       Symbol-Table
Question 14 Explanation:
Symbol tables are data structures that are used by compilers to hold information about source-program constructs. The information is collected incrementally by the analysis phases of a compiler and used by the synthesis phases to generate the target code. Entries in the symbol table contains information about an identifier such as its character string (or lexeme) , its type,its position in storage, and any other relevant information.
 Question 15
Which type of addressing mode, less number of memory references are required?
 A Immediate B Implied C register D indexed E None of the above
Question 15 Explanation:
Excluded for evaluation
 Question 16
How many different Boolean functions of degree n are there?
 A 2​2n B (2​2​)​2 C 2​2n-1 D 2n
Digital-Logic-Design       Boolean-Function
Question 16 Explanation:
There are 2​ n​ different n-tuples of 0s and 1s.
A Boolean function is an assignment of 0 or 1 to each of these 2​ n​ different n-tuples.
Therefore, there are 2​ 2^n different Boolean functions.
Example: How many different Boolean functions of degree 4 are there?
Solution: 16
 Question 17
Consider the equation (146)​ b​ + (313)​ b-2​ = (246)​ 8​ . Which of the following is the value of b?
 A 8 B 7 C 10 D 16
Digital-Logic-Design       Number-Systems
Question 17 Explanation:
(146)7+(317)7-2=(246)8
Substitute 7 in b,
(146)7+(317)7-2=(246)8
(146)7+(317)5=(246)8
(146)7=1*72+4*71+6*70
=49+28+6
=83
(317)5=3*52+1*51+7*50
=75+5+7
= 87
(246)8=2*82+4*81+6*80
=128+32+6
= 166
∴ (146)7+(317)5=(246)8
=83+87
=166
166=166
LHS = RHS equal only if b is 7.
 Question 18
Match List-I with List-II
List-I                                  List-II
(b) CPU                         (ii) Signal
(c) Memory                  (iii) File System
Choose the correct option from those given below:
 A (a)-(i); (b)-(ii); (c)-(iii); (d)-(iv) B (a)-(iii); (b)-(i); (c)-(iv); (d)-(ii) C (a)-(ii); (b)-(i); (c)-(iv); (d)-(iii) D (a)-(ii); (b)-(iv); (c)-(iii);(d)-(i)
Operating-Systems       Memory-Management
Question 18 Explanation:
Disk--> File system
Interrupt → Signal
 Question 19
In the TCP/IP model, encryption and decryption are functions of ____ layer
 A data link B network C Transport D Application
Computer-Networks       TCP/IP-Layers
Question 19 Explanation:
encryption and decryption are functions of presentation layer in the OSI reference model. Here, they were given TCP/IP model. It combines Session, presentation and Application layers into Application layer.
 Question 20
Suppose that a connected planar graph has six vertices, each of degrees four. Into how many regions is the plane divided by a planar representation of this graph?
 A 6 B 8 C 12 D 10
Engineering-Mathematics       Graph-Theory
Question 20 Explanation:
We apply Euler’s formula where r = e−v + 2.
Since each vertex has degree 4, the sum of the degrees is 24.
By the handshaking theorem, 2e = 24 .
so, e = 12.
r = 12−6 + 2
r = 8
Thus we have 8 regions in this planar graph.
 Question 21
Consider a disk system with 100 cylinders. The requests to access the cylinders occur in the following sequence:
4,34,10,7,19,73,2,15,6,20
Assuming that the head is current at cylinder 50, what is the time taken to satisfy all requests if it takes 1ms to move from the cylinder to adjacent one and the shortest seek time first policy is used?
 A 357 ms B 238 ms C 276 ms D 119 ms
Operating-Systems       Disk-Scheduling
Question 21 Explanation:
 Question 22
Which of the following problems is/are decidable problem(s) (recursively enumerable) on a Turing machine M?
(a) G is a CFG with L(G)=∅
(b) There exist two TMs M​1​ and M2​ such that L(M) ⊆{L(M​1​)UL(M​2​)}= language of all TMs
(c) M is a TM that accepts w using a most 2​|w|​ cells of tape
 A (a) and (b) only B (a) only C (a), (b) and (c) D (c) only
Theory-of-Computation       Decidability-and-Undecidability
Question 22 Explanation:
(a): L(G)=∅ is a emptiness problem and emptiness problem for context free languages is decidable.

(b): Recursive: The reason is we can assume L(M2)=∑* and hence any TM (M1) will be definitely subset of L(M2). So we only need to see that M1 is a valid Turing machine and no need to check whether it is subset of L(M2) as it is obviously subset of L(M2)=∑*. Checking validity of Turing machine is always a halting process, hence it is recursive.

(c): L={(M,w)|M is a TM that accepts w using at most 2|w| squares of its tape}.
Recursive: Let m be he number of states in M, and k be the size of the alphabet that M uses, and r=|w|. If M uses at most 2r squares of its tape, then there are at most Alpha=mK2r 2r configurations(why?). If M runs on w for more than α steps, and does not use more than 2r squares of its tape, then M must be in the one configuration at least twice(pigeonhole principle), in which case M would enter an infinite loop on input w. Based on this, we design a machine M* that decides L that works as follows:
M* runs M on w for at most α+1 steps.
If M accepts w which steps with using at most 2r squares, M* halts and accepts.
If M rejects w within α steps with using at most 2r squares, M* halts and rejects.
If M goes beyond 2r squares, M* halts and rejects.
If M does not halt and does not go beyond 2r squares, M* rejects.
Note: To know the definition of configurations and the details, reader may refer to "Introduction to theory of computation Michael Sipser, Chapter 8 Space complexity)
 Question 23
Consider Euler's Φ function given by
Φ(n)=nπp|n(1-(1/p))
Where p runs over all the primes dividing n. What is the value of Φ(45)?
 A 3 B 12 C 6 D 24
Computer-Networks       Network-Security
Question 23 Explanation:
Φ(45) → Φ(9*5)
→ Φ(32 * 5)
→ Φ(32) * Φ(5)
→ Φ(32 - 3,(2-1)) * (5-1)
= 24
Remember Formula:
If p is prime then Φ(p) = (p-1)
and if p is not prime and it's in prime power k from then Φ(pk) = pk - p(k-1)
 Question 24
Consider double hashing of the form
h(k,i)=(h​ 1​ (k)+ih​ 2​ (k)) mod m
Where h​ 1​ (k)=k mod m
h​ 2​ (k)=1+(k mod n)
Where n=m-1and m=701
for k=123456, what is the difference between first and second probes in terms of slots?
 A 255 B 256 C 257 D 258
Data-Structures       Hashing
Question 24 Explanation:
Given h(k,i)=h1(k)+ih2(k)
where h1(k)=k mod m
h2(k)=1+k mod n
where n=m-1 and m=701. For k=123456
h1(k)=123456 mod 701
h1(k)=80
h2(k)=1+(123456 mod 700)
h2(k)=1+256=257
1st probe: i=1
h(k,i)=h1(k)+ih2(k)
h(k,1)=h1(k)+ih2(k)
h(k,1)=80+257=337
h(k,1)=337
2nd probe: i=2
h(k,2)=80+2257
h(k,2)=80+514
h(k,2)=594
∴ Difference h(k,2)-h(k,1)
594-337
257
 Question 25
At a particular time of computation, the value of a counting semaphore is 7. Then 20 P(wait) operations and 15 V(signal) operations are completed on this semaphore. What is the resulting value of the semaphore?
 A 28 B 12 C 2 D 42
Operating-Systems       Semaphores
Question 25 Explanation:
In counting semaphore, Wait operations will decrease the value and signal operations will increase the value.
Initially counting semaphore value is 7.
20 P(wait) operations= -20
15 V(Signal) operation= +15
= 7-20+15
= 2
 Question 26
Software validation mainly checks for inconsistencies between
 A Use cases and user requirements B Implementation and system design blueprints C Detailed specifications and user requirements D Function specifications and use cases
Software-Engineering       Software-configuration-management
Question 26 Explanation:
Software validation checks that the software product satisfies or fits the intended use (high-level checking), i.e., the software meets the user requirements, not as specification artifacts or as needs of those who will operate the software only; but, as the needs of all stakeholders (such as users, operators, administrators, managers, investors, etc.). There are two ways to perform software validation: internal and external. During internal software validation, it is assumed that the goals of the stakeholders were correctly understood and that they were expressed in the requirement artifacts precisely and comprehensively. If the software meets the requirement specification, it has been internally validated. External validation happens when it is performed by asking the stakeholders if the software meets their needs. Different software development methodologies call for different levels of user and stakeholder involvement and feedback; so, external validation can be a discrete or a continuous event.
 Question 27
Shift-reduce parser consists of
(a) input buffer
(b) stack
(c) parse table
choose the correct option from those given below:
 A (a) and (b) only B (a) and (c) only C (c) only D (a), (b) and (c)
Compiler-Design       Parsers
Question 27 Explanation:
Shift-reduce parser consists of
(a) input buffer
(b) stack
(c) parse table
 Question 28
For a statement
A language L ⊆ Σ* is recursive if there exists some Turing machine M
Which of the following conditions is satisfied for any string w?
 A If w ε L, then m accepts w and M will not halt B If w ∉ L, then M accepts w and M will halt by reaching at final state C If w ∉ L, then M halts without reaching to acceptable state D If w ε L, then M halts without reaching to an acceptable state
Theory-of-Computation       Turing-machines
Question 28 Explanation:
If language is recursive then language have Turing machine will always halt in final state (acceptable state) for strings belongs to language and always halt in non final state when string is not in language.
Hence option 3 is correct.
 Question 29
K-mean clustering algorithm has clustered the given 8 observations into 3 clusters after 1st iteration as follows:
C1 : {(3,3), (5,5), (7,7)}
C2 : {(0,6), (6,0), (3,0)}
C3 : {(8,8),(4,4)}
What will be the Manhattan distance for observation (4,4) from cluster centroid C1 in second iteration?
 A 2 B √2 C 0 D 18
Algorithms       K-mean-clustering-algorithm
 Question 30
​What is the output of the following JAVA program?
public class Good{
Private int m;
Public Good(int m){this.m=m;}
public Boolean equals(Good n){return n.m=m;}
public static void main(String args [ ]){
Good m1=new Good(22);
Good m2=new Good(22);
Object S1=new Good(22);
Object S2=new good(22);
System.out.println(m1.equals(m2));
System.out.println(m1.equals(s2));
System.out.println(m1.equals(s2));
System.out.println(s1.equals(m2));
}
}
 A True, True, False, False B True, false, True, false C True, True, False, True D true, False, False, False E None of the above
OOPS       JAVA
Question 30 Explanation:

Note: Question is wrong, Change boolean to int data type then possibility option 4). Marks will be added to all.
 Question 31
In relational database, if a relation R is in BCNF, then which of the following is true about relation R?
 A R is in 4NF B R is not in 1NF C R is in 2Nf and not in 3NF D R is in 2NF and 3NF
Database-Management-System       Normalization
Question 31 Explanation:
If a relation R is in BCNF then R will be in 1NF, 2NF and 3NF. Since the requirement of a BCNF relation is that the left hand side of each functional dependency should be a super key because of this, neither there will be a partial dependency in relation R nor there will be transitive dependency.
 Question 32
In relational database management, which of the following is/are property/properties of candidate key?
P:Uniqueness
Q: Irreducibility
 A P only B Q only C Both P and Q D Neither P nor Q
Database-Management-System       Candidate-key
Question 32 Explanation:
Let K be a subset of the heading of relvar R. Then K is a candidate key (or just key for short) for R if and only if it possesses both of the following properties:
Uniqueness: No valid value for R contains two distinct tuples with the same value for K.
Irreducibility: No proper subset of K has the uniqueness property.
 Question 33
Consider three intensive processes, which requires 10,20 and 30 units of time and arrive at times 0,2 and 6 respectively. how many context switches are needed if the operating system implements a shortest remaining time first scheduling algorithm? Do not count the context switches at time zero ad at the end
 A 4 B 2 C 3 D 1
Operating-Systems       Process-Scheduling
Question 33 Explanation:

Total no.of context switches is 2.
 Question 34
Which of the following statements is/are true?
P: In a scripting language like javaScript, types are typically associated with values, not variables.
Q: It is not possible to show images on a web page without the tag of HTML
Select the correct answer from the given below:
 A P only B Q only C Both P and Q D neither P nor Q
Web-Technologies       Java-Script
Question 34 Explanation:
P : True. Variables are typically not declared in scripting language is, so there is no opportunity to assign them a type.
 Question 35
Match List-I with List-II:
List-I                                                              List-II
(a) Prims's algorithm                          (i)O(V3 logV)
(b) Dijkstra's algorithm                      (ii) O(VE2)
(c) Faster all pairs shortest path     (iii) O(ElogV)
(d) Edmonds-karp algorithm            (iv) O(V2)
 A (a)-(ii); (b)-(iv); (c)-(i); (d)-(iii) B (a)-(iii); (b)-(iv); (c)-(i); (d)-(ii) C (a)-(ii); (b)-(i); (c)-(iv); (d)-(iii) D (a)-(iii); (b)-(i) (c)-(iv); (d)-(ii)
Algorithms       Greedy-and-Dynamic-algorithm
Question 35 Explanation:
Prim’s algorithm→ O(ElgV)
Dijsktra’s algorithm → O(v​ 2​ )
Faster all-pair shortest path→ O(V​ 3​ logV)
Edmonds-karp algorithm → O(VE​ 2​ )
 Question 36
How many address lines and data lines are required to provide a memory capacity of 16K x 16?
 A 10,4 B 16,16 C 14,16 D 4,16
Digital-Logic-Design       Combinational-Circuit
Question 36 Explanation:
16K x 16 means we have 2​ 14​ address lines and 16 data lines.
In order to provide ​ 2 14 address lines we need 14 address lines and in order to provide 16 data lines we need 16 data lines.
 Question 37
Consider the following steps:
S​1​ : Characterize the structure of an optimal solution
S2​ : Computer the value of an optimal solution in bottom-up fashion
Which of the step(s) is/are common to both dynamic programming and greedy algorithms?
 A Only S​1 B Only S​2 C both S​1​ and S​2 D neither S​1​ nor S​2
Algorithms       Dynamic-Programming
Question 37 Explanation:
Dynamic Programming will satisfy both properties but greedy is not following both properties.
 Question 38
Match List-I with List-II:
Where L1 : Regular language
L2 : Context-free language
L3 : Recursive language
L4 : Recursively enumerable language
List-I                                              List-2
(a) L'3 U L4                                 (i) Context-free language
(b) L'2 U L3                                 (ii) Recursively enumerable language
(c) L1* ∩ L2                            (iii) Recursive language
Choose the correct from those given below:
 A (a)-(ii); (b)-(i); (c)-(iii) B (a)-(ii); (b)-(iii); (c)-(i) C (a)-(iii); (b)-(i); (c)-(ii) D (a)-(i); (b)-(ii); (c)-(iii)
Theory-of-Computation       Languages-and-Grammars
Question 38 Explanation:
(a): L3 is a recursive language and we know that recursive languages are closed under complement operation. And union of recursive language and recursively enumerable language is recursively enumerable.
Hence (a) matches with (ii).
(b): Context free language are not closed under complement operation. So consider L2 as recursive language because context free languages are also recursive language so we can say that L2 is recursive language and we know that recursive languages are closed under complement operation.
Now union of ~L2 and L3 will result in recursive language because both ~L2 and L3 are recursive language and recursive languages are closed under union operation.
Hence (b) matches with (iii)
(c): L1 is regular language and regular languages are closed under kleene closure operation.
Hence L​ 1​ * is a regular language. And intersection of L​ 1​ and L​ 2​ results into a regular language.
But, since all regular languages are context free language then we can say that intersection of L​ 1​ and L​ 2​ results into a context free language.
Hence (c) matches with (i).
 Question 39
A fully connected network topology is a topology in which there is a direct link between all pairs of nodes. Given a fully connected network with n nodes, the number of direct links as a function of n can be expressed as
 A n(n+1)/2 B (n+1)/2 C n/2 D n(n-1)/2
Computer-Networks       Topologies
Question 39 Explanation:
In a fully connected network, if there are n nodes in network then each node will be connected with remaining (n-1) nodes. So this way the total number of links will be n(n-1). And since for communication between any two nodes we don’t need two links, they can communicate using a single link between them so the same way we need [n(n-1)]/2 links in a fully connected network.
Ex: Take n=5
n(n-1)/2
= 5(5-1)/2
= 20/2
= 10
 Question 40
Suppose that the register A and register K have the bit configuration. Only the three leftmost bits of A are compared with memory words because K has 1's in these positions. Because of its organization, this type of memory is uniquely suited to parallel seches by data association. This type of memory is known as
 A RAM B ROM C Content addressable memory D Secondary memory
Computer-Organization       Types-of-Memory
Question 40 Explanation:
Content-addressable memory (CAM) is a special type of computer memory used in certain very-high-speed searching applications. It is also known as associative memory or associative storage and compares input search data (tag) against a table of stored data, and returns the address of matching data (or in the case of associative memory, the matching data).
 Question 41
What will be the number of states when a MOD-2 counter is followed by a MOD-5 counter?
 A 5 B 10 C 15 D 20
Digital-Logic-Design       Sequential-Circuits
Question 41 Explanation:
Here, we are multiplying the mod values.
Given mod values are 2 and 5
= 2*5
= 10
 Question 42
In the context of software testing, which of the following statements is/are NOT correct?
P: A minimal test set that achieves 100% path coverage will also achieve 100% statement coverage.
Q: A minimal test set that achieves 100% path coverage will generally detect more faults than one that achieves 100% statement coverage
R: A minimal test set that achieves 100% statement coverage will generally detect more faults than one that achieves 100% branch coverage
 A R only B Q only C P and Q only D Q and R only
Software-Engineering       Software-testing
Question 42 Explanation:
A minimal test set that achieves 100% statement coverage will generally detect more faults than one that achieves 100% branch coverage
 Question 43
Consider the following:
(a) Evolution
(b) Selection
(c) reproduction
(d) Mutation
Which of the following are found in genetic algorithms?
 A (b),(c) and (d) only B (b) and (d) only C (a),(b),(c) and (d) D (a),(b) and (d) only
Artificial-intelligence       Genetic-algorithms
Question 43 Explanation:
Five phases are considered in a genetic algorithm.
1.Initial population
2.Fitness function
3.Selection
4.Crossover
5.Mutation Note: According to official key option-C is correct.
 Question 44
The value of the derivative of the sigmoid function given by
f(x)= 1 / (1+e(-2x)) at x=0 is
 A 0 B 1/2 C 1/4 D ∞
Engineering-Mathematics       Calculus
 Question 45
Consider the poset ({3,5,9,15,24,45},|).
Which of the following is correct for the given poset?
 A There exists a greatest element and a least element B There exists a greatest element but not a least element C There exists a least element but not a greatest element D There does not exist a greatest element and a least element
Engineering-Mathematics       Set-Theory
Question 45 Explanation:
Hasse diagram:

There is no greatest element because this element would have to be a number that all other elements divide. Since our maximal elements are 24 and 45, and they do not divide each other, we do not have a greatest element.
There is no least element because this element would be a number that can divide all other elements. Since our minimal elements are 3 and 5, and they do not divide each other, we do not have a least element.
 Question 46
 A 1 B 2 C 3 D 4
Engineering-Mathematics       Linear-Algebra
 Question 47
Hadoop(a big data tool) works with number of related tools. Choose from the following, the common tools included into Hadoop:
 A MySQl, Google API and Map reduce B Map reduce, Scala and hummer C Map reduce, H base and Hive D Map reduce, hummer and Heron
Question 47 Explanation:
The common tools included into Hadoop are mainly
Map reduce
H base
Hive
 Question 48
Consider the following properties with respect to a flow network G=(V,E) in which a flow is a real-valued function f:VxV→ R
P1 : For all u,vεV, f(u,v)= -f(v,u)
P2 : ΣvεV f(u,v)=0 for all uεV
Which one of the following is/are correct?
 A Only P1 B Only P1 C Both P1 and 2 D Neither P1 nor P2
Engineering-Mathematics       Relations-and-Functions
Question 48 Explanation:
A pseudo-flow is a function f : V × V → ℝ that satisfies the following two constraints for all nodes u and v:
Skew symmetry: Only encode the net flow of units between a pair of nodes u and v that is:
f(u, v) = −f(v, u).
Capacity constraint: An arc's flow cannot exceed its capacity, that is: f (u, v) ≤ c(u, v).
Given a pseudo-flow f in a flow network, it is often useful to consider the net flow entering a given node v, that is, the sum of the flows entering v.
The excess function xf : V → ℝ is defined by xf (u) = ∑v∈V f (v, u). A node u is said to be active if xf (u) > 0, deficient if xf (u) < 0 or conserving if xf (u) = 0.
These final definitions lead to two strengthenings of the definition of a pseudo-flow:
A pre-flow is a pseudo-flow that, for all v ∈ V \{s}, satisfies the additional constraint:
Non-deficient flows: The net flow entering the node v is non-negative, except for the source, which "produces" flow. That is: xf (v) ≥ 0 for all v ∈ V \{s}.
A feasible flow, or just a flow, is a pseudo-flow that, for all v ∈ V \{s, t}, satisfies the additional constraint:
Flow conservation: The net flow entering the node v is 0, except for the source, which "produces" flow, and the sink, which "consumes" flow. That is: xf (v)=0 for all v∈V \{s, t}.
The value of a feasible flow f, denoted | f |, is the net flow into the sink t of the flow network. That is, | f | = xf (t).
 Question 49
Let Aα0 denotes the α-cut of a fuzzy set A at α0. If α1 < α2 , then
 A Aα1 ⊇ Aα2 B Aα1 ⊃ Aα2 C Aα1 ⊆ Aα2 D Aα1 ⊂ Aα2
Engineering-Mathematics       Fuzzy-logic
Question 49 Explanation:
 Question 50
Which of the following statements is/are true with regard to various layers in the Internet stack? P: At the link layer, a packet of transmitted information is called a frame Q: At the network layer, a packet of transmitted information is called a segment
 A P only B Q only C P and Q D Neither P nor Q
Computer-Networks       TCP/IP-Layers
Question 50 Explanation:

 Question 51
Consider the following C-code fragment running on a 32-bit x86 machine:

typedef struct

{

union

{

Unsigned char a;

unsigned short b;

}

unsigned char c;

}S;

S B[10];

S*p=&B[4];

S*q=&B[5];

p→ U.b=0x1234;

/* structure S takes 32-bits */

If M is the value of q-p and N is the value of ((int) & (p→ c))-((int)p), then (M,N) is

 A (1,1) B (3,2) C (1,2) D (4,4)
C-Programming       Structure-and-Union
Question 51 Explanation:
#include
typedef struct{
union
{
unsigned char a;
unsigned short b;
}U;
unsigned char c;
}S;
int main()
{
printf("Hello World");
S B[10]; // declaring array of 10 structures
S*p=&B[4]; // Assigning 4th array value to pointer p
S*q=&B[5]; // Assigning 5th array value to pointer q
p-> U.b=0x1234; // Assigning a value to 4th structure array element's union short b
printf("q-p %u\n",sizeof(p)); // value is 1, as pointer subtraction formula is (address of q - address of p) / size of structure
printf("%d\n",((int) & (p->c))-((int)p)); // value is 2 the address difference between p starting address and ‘c’ address, between them is only short integer of 2 bytes
return 0;
}
 Question 52
Consider an LPP given as

Max Z=2x1 - x2 + 2x3

Subject to the constraints

2x1 + x2 ≤ 10

x1 + 2x2 - 2x3 ≤ 20

x1 + 2x3 ≤ 5

x1, x2, x3 ≥ 0

What shall be the solution of the LPP after applying first iteration of the Simplex Method?

 A x1=5/2, x2=0, x3=0, Z=5 B x1=0, x2=0, x3=5/2, Z=5 C x1=0, x2=5/2, x3=0, Z= -5/2 D x1=0, x2=0, x3=10, Z=20
Engineering-Mathematics       Combinatorics
 Question 53
A web application and its support environment has not been fully fortified against attack. Web engineers estimate that the likelihood of repelihood an attack is only 30 percent. The application does not contain sensitive or controversial information, so the threat probability is 25 percent. What is the integrity of the web application?
 A 0.625 B 0.725 C 0.775 D 0.825
Engineering-Mathematics       Probability
 Question 54
Which of the following terms best describes Git?
 A Issue Tracking System B Integrated Development Environment C Distributed Version Control System D Web-Based Repository Hosting Service
Web-Technologies       Git
Question 54 Explanation:
Git is a distributed version control system for tracking changes in source code during software development. It is designed for coordinating work among programmers, but it can be used to track changes in any set of files. Its goals include speed, data integrity, and support for distributed, non-linear workflows.
 Question 55
How can the decision algorithm be constructed for deciding whether context-free language L is finite?
(a) By Constructing redundant CFG in CNF generating language L
(b) By constructing non-redundant CFG G in CNF generating language L
(c) By constructing non-redundant CFG in CNF generating language L-{∧} (∧ stands for null)
Which of the following is correct?
 A (a) only B (b) only C (c) only D None of(a),(b) and (c)
Theory-of-Computation       Context-Free-Grammar
Question 55 Explanation:
To test whether L(G) is finite, use the CNF conversion approach to find a CFG G'=(V', T, P', S) in CNF and with no useless symbols, generating L(G)-{ε}.
L(G') is finite if and only if L(G) is finite. A simple test for finiteness of a CNF grammar with no useless symbols is to draw a directed graph with a vertex for each variable and an edge from A and B if there is a production of the form A→BC or A→ CB for any C. Then the language generated is finite if and only if this graph has no cycles.
 Question 56
For which values of m and n does the complete bipartite graph km,n have a Hamilton circuit?
 A m≠n, m, n≥2 B m≠n, m, n≥3 C m=n, m, n≥2 D m=2, m, n≥3
Engineering-Mathematics       Graph-Theory
Question 56 Explanation:
let G=(A|B,E) be a bipartite graph. Let G be Hamiltanion.
Then |A|=|B|
That is, there is the same number of vertices in A as there are in B.
 Question 57
 A ARP B DNS C RARP D ICMP
Question 57 Explanation:
 Question 58
The RSA encryption algorithm also works in reverse, that is, you can encrypt a message with the private key and decrypt it using the public key. This property is used in
 A Intrusion detection systems B Digital signatures C Data Compression D Certification
Computer-Networks       Network-Security
Question 58 Explanation:
Explanation:In digital signature the message is encrypted using the sender's private key and decrypted by the receiver using the sender's public key.

 Question 59
Which of the following features is supported in the relational database model?
 A Complex data-types B Multivalued attributes C Association with multiplicities D Generalization relationship
Database-Management-System       Relational-databases
 Question 60
Which of the following statements is/are TRUE?
P: In software engineering, defects that are discovered earlier are more expensive to fix
Q: A software design is said to be a good design, if the components are strongly cohesive and weakly coupled
Select the correct answer from the options given below:
 A P only B Q only C P and Q D Neither P nor Q
Software-Engineering       Software-design
Question 60 Explanation:
Statement-1: Earlier the defect is found lesser is the cost of defect. For example if error is found in the requirement specifications during requirements gathering and analysis, then it is somewhat cheap to fix it. The correction to the requirement specification can be done and then it can be re-issued.

 Question 61
For a magnetic disk with concentric circular tracks, the seek latency is not linearly proportional to the seek distance due to
 A Non-Uniform distribution of requests B arm starting or stopping inertia C higher capacity of tracks on the periphery of the plate D use of unfair arm scheduling policies
Computer-Organization       Secondary-Memory
Question 61 Explanation:
For a magnetic disk with concentric circular tracks, the seek latency is not linearly proportional to the seek distance due to arm starting or stopping inertia.
 Question 62
How many states are there in a minimum state automata equivalent to regular expression given below?
regular expression is a*b(a+b)
 A 1 B 2 C 3 D 4
Theory-of-Computation       Regular-Expression
Question 62 Explanation:
L={ba,bb,aba,abb,...}
 Question 63
How many bit strings of length ten either start with a 1 bit or end with two bits 00?
 A 320 B 480 C 640 D 768
Digital-Logic-Design       Number-Systems
Question 63 Explanation:
→ Number of bit strings of length 10 that start with 1: 29 = 512.
→ Number of bit strings of length 10 that end with 00: 28 = 256
→ Number of bit strings of length 10 that start with 1 and end with 00: 27 = 128
→ Applying the subtraction rule, the number is 512+256-128 = 640
 Question 64
Consider that a process has been allocated 3 frames and has a sequence of page referencing 1,2,1,3,7,4,5,6,3,1
What shall be the difference i page faults for the above string using the algorithm of LRU and Optimal page replacement for referencing the string?
 A 2 B 0 C 1 D 3
Operating-Systems       Page-Replacement-algorithm
Question 64 Explanation:

 Question 65
Software products need are adaptive maintenance for which of the following reasons?
 A To rectify bugs observed while the system is in use. B When the customers need the product to run on new platforms C To support the new features that users want it to support D To overcome wear and tear caused by the repeated use of the software.
Software-Engineering       Software-configuration-management
Question 65 Explanation:
Maintenance: Maintenance can be referred as a process of enhancement in the software product according to the changing requirements of users.
4 types of maintenance:
1. Adaptive – modifying the system to cope with changes in the software environment (DBMS, OS).
2. Perfective – implementing new or changed user requirements which concern functional enhancements to the software
3. Corrective – diagnosing and fixing errors, possibly ones found by users.
4. Preventive – increasing software maintainability or reliability to prevent problems in the future.
 Question 66
Consider the following C++ function f() :
unsigned int f(unsigned int n)
{
unsigned int b=0;
while(n)
{
b+=n&1;
n>>=1;
}
return b;
}
The function f() returns the int that represents the___p___in the binary representation of positive integer n, where P is
 A number of 0's B number of bits C number of consecutive 1's D number of 1's
Programming-in-c++       Functions
Question 66 Explanation:
& operator does the binary and operation of both value and 1
when b += n & 1 is given
n and 1, both will be converted to binary and binary & operation is calculated
any number & 000000001
it will only compare the last bit of both numbers, if both right most bit is 1 then the value is incremented by 1 and the number n is right shifted that means it loses the value of right most bit and again new right most bit is binary anded with 1.
So the value is nothing but the number of 1's of the binary format of number.
 Question 67
The fault can be easily diagnosed in the microprogram control unit using diagnostic tools by maintaining the contents of
 A Flags and Counters B Registers and counters C Flags and registers D Flags, registers and counters
Computer-Organization       Microprogrammed-Control-Unit
Question 67 Explanation:
The fault can be easily diagnosed in the microprogram control unit using diagnostics tools by maintaining the contents of flags, registers and counters.
 Question 68
The minimum number of page frames that must be allocated to a running process in a virtual memory environment is determined by
 A Page size B Physical size of memory C The instruction set architecture D Number of processes in memory
Operating-Systems       Virtual Memory
Question 68 Explanation:
→ Based on Instruction Set Architecture each process can be need minimum no. of pages.
→ An ISA permits multiple implementations that may vary in performance, physical size and monetary cost.
 Question 69
A processor can support a maximum memory of 4 GB where memory is word addressable and a word is 2 bytes. What will be the size of the address bus of the processor?
 A At least 28 bits B At least 2 bytes C At least 31 bits D Minimum 4 bytes
Question 69 Explanation:
Maximum Memory = 4GB = 232 bytes
Size of a word = 2 bytes
Therefore, Number of words = 232 / 2 = 231
So, we require 31 bits for the address bus of the processor.
 Question 70
Match List-I with List-II:
List-I                                                   List-II
(a) Greedy best-first                     (i) Minimal cost (p)+h(p)
(b) Lowest cost-firs                     (ii) Minimal h(p)
(c) A* algorithm                            (iii) Minimal cost (p)
Choose the correct option from those given below:
 A (a)-(i); (b)-(ii); (c)-(iii) B (a)-(iii);(b)-(ii); (c)-(i) C (a)-(i); (b)-(iii); (c)-(ii) D (a)-(ii); (b)-(iii); (c)-(i)
Algorithms       Greedy-approach
Question 70 Explanation:
A* is an informed search algorithm, or a best-first search, it aims to find a path to the given goal node having the smallest cost. A* selects the path that minimizes
f(n)=g(n)+h(n)
where n is the next node on the path, g(n) is the cost of the path from the start node to n, and h(n) is a heuristic function that estimates the cost of the cheapest path from n to the goal.
Greedy Best First Search tries to expand the node that is closest to the goal, on the grounds that this is likely to lead to a solution quickly. Thus, it evaluates nodes by using just the heuristic function
f(n) = h(n).
 Question 71
Which of the following are the primary objectives of risk monitoring in software project tracking?
P: To assess whether predicted risks do, in fact, occur
Q: To ensure that risk aversion steps defined for the risk are being properly applied
R: To collect information that can be used for future risk analysis
 A Only P and Q B Only P and R C Only Q and R D All the P,Q,R
Software-Engineering       Software-configuration-management
Question 71 Explanation:
Risk monitoring is a project tracking activity with three primary objectives:
(1) to assess whether predicted risks occur.
(2) to ensure that risk aversion steps defined for the risk are being properly applied; and
(3) to collect information that can be used for future risk analysis.
 Question 72
On translating the expression given below into quadruple representation, how many operations are required? (i*j)+(e+f)*(a*b+c)
 A 5 B 6 C 3 D 7
Compiler-Design       Intermediate-code-generator
Question 72 Explanation:
T1 = (i*j)
T2=(e+f)
T3=(a*b)
T4= (T3+c)
T5=T2 * T4
T6=T1 + T5
Hence 6 operations are required.
 Question 73
Consider the following statements regarding 2D transforms in computer graphics:

 A Both S1 and S2 are true B Only S1 is true C Only S2 is true D Both S1 and S2 are false
Computer-Organization       Graphics
 Question 74
Which of the following UNIX/Linux pipes will count the number of lines in all the files having .c and .h as their extension in the current working directory?
 A cat *.ch | wc -l B cat *.[c-h] | wc -l C cat *.[ch] | ls -l D cat *.[ch] | wc -l
Operating-Systems       UNIX-Operating-System
Question 74 Explanation:
wc→ It performs word count.
cat→ Display content of a file.
| → pipe symbol. It passes the output of left command to right command.
cat *.[ch] amd cat *.[c-h] both will display the content of the two extensions .c files and .h files however [c-h] is the range matcher and can display the file contents *.d, *.e, *.f *.g and *.h files as well.
cat *.[ch] | wc -l
 Question 75
The parallel bus arbitration technique uses an external priority encoder and a decoder. Suppose, a parallel arbiter has 5 bus arbiters. What will be the size of priority encoder and decoder respectively?
 A 4x2, 2x4 B 2x4, 4x2 C 3x8, 8x3 D 8x3, 3x8
Digital-Logic-Design       Combinational-Circuit
Question 75 Explanation:

 Question 76
Which of the following is best running time to sort n integers in the range 0 to n2-1
 A O(log n) B O(n) C O(n log n) D O(n2)
Algorithms       Sorting
Question 76 Explanation:
Using merge, heap sort will get O(nlogn)
But using radix sort will get in linear time only. O(n)
 Question 77
Following table has two attributes Employee_id and Manager_id, where Employee_id is a primary key and manager_id is a foreign key referencing Employee_id with on-delete cascade:

On deleting the table (20,40), the set of other tuples that must be deleted to maintain the referential integrity of table is
 A (30,35) only B (30,35) and (35,20) only C (35,20) only D (40,45) and (25,40) only
Database-Management-System       Constraints
Question 77 Explanation:
If (20, 40) is deleted then the entry in manager_id containing 20 value will violate the referential integrity constraint so entry (35,20) is deleted because of deletion of (20,40).
Similarly entry (30,35) is deleted because of the deletion of entry (35,20).
After deletion of entry (30,35) referential integrity is maintained in given relation so no further deletion are made.
Hence correct option is option(2).
 Question 78
Which of the following is an application of depth-first search?
 A Only topological sort B Only strongly connected components C Both topological sort and strongly connected components D Neither topological sort not strongly connected components
Data-Structures       Graphs-and-Tree
Question 78 Explanation:
Both topological sort and strongly connected components are applications of DFS.
Topological sort time complexity is O(V+E)
Strongly connected components time complexity is O(V+E)
DFS time complexity is O(V+E)
 Question 79
Consider the following grammar:
S→ XY
X→ YaY | a and y →  bbX
Which of the following statements is/are true about the above grammar?
(a) Strings produced by the grammar can have consecutive three a's
(b) Every string produced by the grammar have alternate a and b
(c) Every string produced by the grammar have at least two a's
(d) Every string produced by the grammar have b's in multiple of 2.
 A (a) only B (b) and (c) only C (d) only D (c) and (d) only
Theory-of-Computation       Languages-and-Grammars
Question 79 Explanation:
L= { abba, bbaabbabba,.........................}
Statement (a) is not correct because the grammar can generate two consecutive a’s but not three consecutive a’s.
Statement (b) is not correct because the grammar can generate two b’s together it means that there is no alteration of “a” and “b”.
Statement (c) is correct because every string produced by the grammar have at least two a's. Statement (d) is correct because every string produced by the grammar have b's in multiple of 2.
 Question 80
Consider a raster system with resolution 640 by 480. What size is frame buffer (in bytes) for this system to store 12 bits per pixel?
 A 450 kilobytes B 500 Kilobytes C 350 kilobytes D 400 kilobytes
Computer-Organization       Graphics
Question 80 Explanation:
8 bits = 1 byte.
A frame-buffer size of the systems are as follows:
= (640 x 480 x 12) bits / 8
= 450KB
 Question 81
Using the phong reflectance model, the strength of the specular highlight is determined by the angle between
 A The view vector and the normal vector B The light vector and the normal vector C The light vector and the reflected vector D the reflected vector and the view vector
Computer-Graphics       Phong-Reflectance-Model
Question 81 Explanation:
Specular highlights on objects appear, because the light reflected from the object hits viewer. Sometimes, we are hit directly by the light and the highlight appears to be very intense, and sometimes we are hit so slightly, that we basically don't see the specular highlight. The strength of this highlight depends on the cosine of the angle between the reflected vector and vector taken from the point at object to the viewer's position:

 Question 82
With respect to relational algebra, which of the following operations are included from mathematical set theory
(a) join
(b) Intersection
(c) Cartisian product
(d) Project
 A (a) and (b) B (b) and (c) C (c) and (d) D (b) and (d)
Database-Management-System       Relational-Algebra
Question 82 Explanation:
Only Intersection and cartesian product operations are included from mathematical set theory. The Join and Project operations are not there in mathematical set theory.
 Question 83
How many cards must be selected from a standard deck of 52 cards to guarantee that at least three hearts are present among them?
 A 9 B 13 C 17 D 42
Engineering-Mathematics       Combinatorics
 Question 84
Which of the following is an example of unsupervised neural network?
 A Back propagation network B Hebb network C Associative memory network D Self-organizing feature map
Artificial-intelligence       Artificial-neural-networks(ANN)
Question 84 Explanation:
A self-organizing map (SOM) or self-organizing feature map (SOFM) is a type of artificial neural network (ANN) that is trained using unsupervised learning to produce a low-dimensional (typically two-dimensional), discretized representation of the input space of the training samples, called a map, and is therefore a method to do dimensionality reduction. Self-organizing maps differ from other artificial neural networks as they apply competitive learning as opposed to error-correction learning (such as backpropagation with gradient descent), and in the sense that they use a neighborhood function to preserve the topological properties of the input space.
 Question 85
There are many sorting algorithms based on comparison. The running time of heap sort algorithm is O(nlogn). Let P, but unlike Q, heapsort sorts in place where (P,Q) is equal to
 A Merge sort, Quick sort B Quick sort, Insertion sort C Insertion sort, Quick sort D insertion sort, Merge sort
Algorithms       Sorting
Question 85 Explanation:
This is an ambiguous question.
Method-1:
Mergesort is having best,average and worst case time complexity is O(nlogn) as like hep sort. Quick sort is also same like heap and merge except worst case time complexity is O(n2). According to question, P is merge sort and Q is quick sort.
Method-2:
Heap sort and insertion sort is not following divide and conquer technique. So, it is same like P.
Merge sort follows Divide and Conquer. So, it is not like Q.
Note: Official Key given answer is Option-4
 Question 86
You are designed a link layer protocol for a link with bandwidth of 1 Gbps (109 bits/second) over a fiber link with length of 800 km. Assume the speed of light in this medium is 200000 km/second. What is the propagation delay in this link?
 A 1 millisecond B 2 millisecond C 3 millisecond D 4 millisecond
Computer-Networks       Transmission-and-Propagation-Delay
Question 86 Explanation:
Tp=Distance/Time
=800/200000
=4*10-3 sec
= 4 milliseconds
 Question 87
Consider the following two statements with respect to IPv4 in computer networking:
P: The loopback(IP) address is a member of class B network
Q: The loopback(IP) address is used to send a packet from host to itself
What can you say about the statements P and Q?
 A P-True: Q-False B P-False; Q-True C P-True; Q-True D P-False; Q-false
Question 87 Explanation:
Explanation: The loopback(IP) address is a member of class A network. Any address between the range 127 . 0. 0. 0 to 127.255.255.255 can be used a loopback address but we can’t use 127 . 0. 0. 0 and 127.255.255.255 as loopback addresses.
The loopback(IP) address is used to send a packet from host to itself
 Question 88
The STRIPS representation is
 A a feature-centric representation B an action-centric representation C a combination of feature-centric and action-centric representation D a hierarchical feature-centric representation
Artificial-intelligence       STRIPS
Question 88 Explanation:
The STRIPS representation for an action consists of
→The precondition, which is a set of assignments of values to features that must be true for the action to occur, and
→The effect, which is a set of resulting assignments of values to those primitive features that change as the result of the action.
 Question 89
Which of the following has the same expressive power with regard to relational query language?
(a) Relational algebra and Domain relational calculus
(b) Relational algebra and Tuple relational calculus
(c) Relational algebra and Domain relational calculus restricted to safe expression
(d) Relational algebra and Tuple relational calculus restricted to safe expression
 A (a) and (b) only B (c) and (d) only C (a) and (c) only D (b) and (d) only
Database-Management-System       Relational-Algebra
Question 89 Explanation:
Relational algebra, Domain relational calculus restricted to safe expression and Tuple relational calculus restricted to safe expression have the same expressive power.
 Question 90
Which of the following statements is/are true
P: An XML document with correct as specified by W3C is called “well formed”.
Q: An XML documented validated against a DTD is both “Well-Formed” and “valid”.
R: is syntactically correct declaration for the version of an XML document.
Select the correct answer from the options given below:
 A P and Q only B P and R only C Q and R only D All of P,Q and R
Web-Technologies       XML
Question 90 Explanation:
→ A XML document is said to be well- formed if it has correct syntax like tags are case sensitive, elements must have closing tags, elements must be properly nested etc.
→ But when we associate a well formed XML document with a DTD( in which we define the structure of a document) and if that XML document validates all the definitions defined in DTD then that XML document is called as “valid” XML document.
→ Always remember that a “valid” XML document is also a “well-formed” XML document but a “well-formed” XML document is not necessarily a “valid” XML document
→ < ? xml version="1.0" encoding="UTF-8" ? > is syntactically correct declaration for the version of an XML document.
 Question 91
Consider the following pseudo-code fragment in which an invariant for the loop is " m*xk =pnand k ≥ 0 " (Here, p and n are integer variables that have been initialized):
/* Pre-conditions:p ≥ 1 ∧ n ≥ 0 */
/* Assume that overflow never occurs */
int x=p; int k=n; int m=1;
while(k< >0)
{
if(k is odd) then m=m*x;
x=x*x;
k=⌊(k/2)⌋; /* floor(k/2) */
}
Which of the following must be true at the end of the while loop?
 A x=pn B m=pn C p=xn D p=mn
Programming       Control-Statement
Question 91 Explanation:
Option-1: It is not correct because of x=plog n
Option-3 and 4: These two statements are not correct because they were given left side value is much smaller than the right side.
So, option-2 is correct.
 Question 92
The component in MVC is responsible for
 A User interface B Security of the system C Business logic and domain objects D Translating between user interface actions/events and operation on the domain objects
Web-Technologies       MVC
Question 92 Explanation:
"MVC" stands for "Model-View-Controller" and refers to three different realms of responsibility in the design of a graphical user interface.
When the MVC pattern is applied to a component, the model consists of the data that represents the current state of the component.
The view is simply the visual presentation of the component on the screen.
And the controller is the aspect of the component that carries out actions in response to events generated by the user (or by other sources such as timers).
The idea is to assign responsibility for the model, the view, and the controller to different objects.
 Question 93
Consider the game tree given below:

 A 4 B 7 C 11 D 12
Data-Structures       Graphs-and-Tree
Question 93 Explanation:

 Question 94
Suppose that a computer program takes 100 seconds of execution time on a computer with multiplication operation responsible for 80 seconds of this time. How much do you have to improve the speed of multiplication operation if you are asked to execute this program four times faster.
 A 14 times faster B 15 times faster C 16 times faster D 17 times faster
Computer-Organization       Speed
Question 94 Explanation:
Total execution time of a program = time to execute multiplication operation + time to perform some other operations
100 = 80 +time to perform some other operations
time to perform some other operations = 20
Now they are saying that improve the speed of multiplication operation if you are asked to execute this program four times faster i.e.
New Total execution time of a program = 100/4
= 25
And according to question we have to keep the time to perform some other operations as it is i.e.20.
Hence time to perform multiplication operation after modification = (New Total execution time of a program - time to perform some other operations)
= 25-20
= 5
So the speed of multiplication operation is improved by 80/5 time = 16 times.
 Question 95
Which of the following are not shared by the threads of the same process?
(a) Stack
(b) Registers
(d) Message Queue
 A (a) and (d) B (b) and (c) C (a) and (b) D (a), (b) and (c)
Question 95 Explanation:

 Question 96
Consider the following statements:
S1 : For any integer n>1, aΦ(n) = 1(mod n) for all a ∊ Z*n, where Φ(n) is euler’s phi function.
S2 : If p is prime, then ap = 1(mod p) for all a ∊ Z*p
Which one of the following is are correct:
 A Only S1 B Only S2 C Both S1 and S2 D Neither S1 nor S2
Computer-Networks       Network-Security
Question 96 Explanation:
Euler's theorem (also known as the Fermat–Euler theorem or Euler's totient theorem) states that if ‘n’ and ‘a’ are coprime positive integers, then aΦ(n) = 1(mod n)
So the S1 is true.
According to Fermat's Little Theorem,
Let ‘p’ be a prime and ‘a’ any integer, then ap = a (mod p). So S2 is false.
 Question 97
You need 500 subnets, each with about 100 usable host addresses  per subnet. What network mass will you assign using a class B network address?
 A 255.255.255.252 B 255.255.255.128 C 255.255.255.0 D 255.255.254.0
Question 97 Explanation:
Explanation: We know that in class B addressing we have 16-bit network ID and !6-bits for host ID.
Since in question 500 subnets are required. Since 29 = 512, So we need to take 9 bits from host id part of class B addressing in order to provide 500 subnets and with remaining 7 bits of host id we can easily 100 usable hosts per subnet because 27 = 128.

Since we know that Subnet mask contains 1’s in subnet id part and the 0's in host ID part. Hence subnet mask is:
11111111 . 11111111 . 11111111 . 10000000
In decimal form it can be represented as:
255 . 255 . 255 . 128
c
 Question 98
The ability to inject packets into the internet with false source address is known as :
 A Man-in-the-Middle attack B IP phishing C IP sniffing D IP Spoofing
Computer-Networks       Network-Security
Question 98 Explanation:
Man-in-the-Middle Attack: It is an attack where the attacker secretly relays and possibly alters the communications between two parties who believe they are directly communicating with each other.
IP Spoofing: is the creation of Internet Protocol (IP) packets with a false source IP address, for the purpose of impersonating another computing system.
 Question 99
Consider the complexity class CO-NP as the set of languages L such that L’ ε NP, and the following two statements:
S1 : P ⊆ CO-NP
S2 : If NP ≠ CO-NP, then P ≠ NP
Which of the following is/are correct?
 A Only S1 B Only S2 C Both S1 and S2 D Neither S1 nor S2
Algorithms       P-NP
There are 99 questions to complete.