Recursively enumerable languages are closed under concatenation,union,homomorphism but not closed under complementation

The language that can be recognized by a finite automata is called regular language.And regular language is closed under reversal

Let's check option wise,
Option a is false because string “aa” is generated by the given grammar which does not contain b’s.
Option b is false because string “aa” is generated by the given grammar which contains consecutive a’s.
Option d is false because string “aba” contains the last symbol as ‘a’ but not generated by the grammar.
Option c is also false because string “aba” contains two a’s but not generated by the grammar.

The pigeonhole principle states that if you have fewer holes than objects then at least one holes has multiple objects in it.It states that put one object in each hole and then there must exist at least one hole which must have more than one object.
In the theory of formal languages in computability theory, a pumping lemma or pumping argument states that, for a particular language to be a member of a language class, any sufficiently long string in the language contains a section, or sections, that can be removed, or repeated any number of times, with the resulting string remaining in that language. The proofs of these lemmas typically require counting arguments such as the pigeonhole principle. Hence, the logic of pumping lemma is a good example of the pigeonhole principle.

First-in-first-out scheduling algorithms are non preemptive scheduling algorithms because in this the process is served according to first come first served manner.

An opcode (abbreviated from operation code), also known as instruction machine code, is the portion of a machine language instruction that specifies the operation to be performed. Beside the opcode itself, most instructions also specify the data they will process, in the form of operands.

The process is selected by the scheduler and then it is the dispatcher who gives the control of the CPU to the process selected by the scheduler

Cache operation is based on the principle of locality of reference. There are two ways with which data or instruction is fetched from main memory and get stored in cache memory. These two ways are the following:
->Spatial locality
->Temporal locality

Component of database includes indexes, data dictionary, metadata, description. But reports are not components. It is generated by user according to their need.

Database normalization is the process of structuring the relational database in accordance with the series of so called normal forms in order to reduce data redundancy and improve data integrity.

A relation is in 2NF or second normal form if there is no partial dependencies in a relation.

Relational algebra is procedural query language.

An array is collection of items stored at contiguous memory locations. The idea is to store multiple items of same type together. This makes it easier to calculate the position of each element by simply adding an offset to a base value, i.e., the memory location of the first element of the array
All of the above given operations can be applied on arrays.

Option c is false because if non leaf node is root node then it can have atleast two children

A compiler takes the program code (source code) and converts the source code to a machine language module (called an object file).

Option a is correct. Option b is correct because arr[i] is equivalent to *(arr+i).

The output cannot be computed because there is no terminating condition in the function mNum(), and so the function will fall into infinite loop whatever value is given;

The output is ohitrrow froablu or

There are 8 software interrupts in 8085 microprocessor.

Race condition occurs if more than one processes is inside the critical section. So to avoid race condition only 1 process should be allowed inside the critical section.

For 8085: Stack pointer is a special purpose 16-bit register in the Microprocessor, which holds the address of the top of the stack.

Routing, inter-networking and congestion control are the functionality of network layer but error correction is not the functionality of network layer.

An endpoint of an inter-process communication flow across a computer network is called the socket.

Transport layer protocol is associated to end to end communication
Network layer protocol is associated to process to process or host to host communication.
Data link layer protocol is associated to node to node communication.

When a packet has to travel from one end system to another, it first faces the queuing delay when there are multiple packets which are to be sent, then it faces the transmission delay to convert the packet into bits to be transmitted, and then it faces the propagation delay to propagate the bits through.

When a packet has to travel from one end system to another, it first faces the queuing delay when there are multiple packets which are to be sent, then it faces the transmission delay to convert the packet into bits to be transmitted, and then it faces the propagation delay to propagate the bits through.

The value of x can be any real no. but [x] will be only integral part of x. Hence x - [x] will be always fractional part of x.

The mean of the binomial distribution is np and the variance of binomial distribution is np(1-p).

The mean of the exponential distribution is 1/λ .

The mean and variance of the poisson distribution is same and it is λ . So the ratio of mean to variance will be λ/λ = 1.

The memoryless property (also called the forgetfulness property) means that a given probability distribution is independent of its history. Any time may be marked down as time zero.
If a probability distribution has the memoryless property the likelihood of something happening in the future has no relation to whether or not it has happened in the past. The history of the function is irrelevant to the future.
The exponential distribution has the property of being memoryless.

In probability theory and statistics, the beta distribution is a family of continuous probability distributions defined on the interval [0, 1] parameterized by two positive shape parameters, denoted by α and β, that appear as exponents of the random variable and control the shape of the distribution.
The expected value (mean) (μ) of a Beta distribution random variable X with two parameters α and β is a function of only the ratio β/α of these parameters:

In the theory of probability and statistics, a Bernoulli trial (or binomial trial) is a random experiment with exactly two possible outcomes, "success" and "failure", in which the probability of success is the same every time the experiment is conducted.

The covariance cov(X,Y) of two independent random variables X and Y is 0.

The set of all possible outcomes for an experiment is called a sample space.

Classroom communication must be student centric because teacher should come to the class for teaching to student. He does not take general or his personal topics. He has to find the need of students. Teacher should also check abilities, interests, and learning styles. On this basis, he has to communicate to his students.

The term "group communication" refers to the messages that are exchanged by group members. These messages, whether verbal or nonverbal, are important to groups because it is through the exchange of messages that group members participate, maintain the group identity, determine goals, motivate participation, and do the many things that keep the group intact

When you as teacher gives the opportunity to your students to talk and interact, you should not allow to give argument. . So, he should motivate students for generating new ideas.

4.3700×(10^-2) = 0.043700 =0.0437 = .0437 . Hence the no. of significant digits in the given no. is 4.

Applied research aims at finding a solution for an immediate problem facing a society, or an industrial/business organisation

Analysis of variance, a statistical method in which the variation in a set of observations is divided into distinct components.

To qualify as good research, the process must have certain characteristics and properties: it must, as fair as possible, be controlled, rigorous, systematic, valid and verifiable, empirical and critical.

The aim of a qualitative research project may vary with the disciplinary background, such as a psychologist seeking in-depth understanding of human behavior and the reasons that govern such behavior for example. Qualitative methods are best for researching many of the why and how questions of human experience, in making a decision for example (not just what, where, when, or "who"); and have a strong basis in the field of sociology to understand government and social programs

According to the Principle of Replication, the experiment should be repeated more than once. Thus, each treatment is applied in many experimental units instead of one. By doing so the statistical accuracy of the experiments is increased. ... The entire experiment can even be repeated several times for better results.

E(3X + 2Y) = 3E(X) + 2E(Y) = 3*5 + 2*-3 = 15 - 6 = 9

Chebyshev's inequality is useful for interpreting variances.

Continuous random variables have numeric values that can be any number in an interval. For example, the (exact) weight of a person is a continuous random variable. Foot length is also a continuous random variable. Continuous random variables are often measurements, such as weight or length.