## GATE 1987

Question 1 |

In a microprocessor-based system, if a bus (DMA) request and an interrupt request arrive simultaneously, the microprocessor attends first to the bus request.

True. | |

False. |

Question 2 |

Data transfer between a microprocessor and an I/O device is usually faster in memory-mapped-I/O scheme than in I/O-mapped - I/O scheme.

True | |

False |

Question 3 |

It is possible to construct a binary tree uniquely whose pre-order and post-order traversals are given?

True | |

False |

Question 4 |

The union of two equivalence relations is also an equivalence relation.

True | |

False |

Reflexive ∪ Reflexive = Reflexive

Symmetric ∪ Symmetric = Symmetric

Transitive ∪ Transitive ≠ Transitive

Since Transitivity does not satisfy union, so union of two equivalence relation is not an equivalence relation.

Question 5 |

There is a linear-time algorithm for testing the planarity of finite graphs.

True | |

False |

Question 6 |

Every infinite cyclic group is isomorphic to the infinite cyclic group of integers under addition.

True | |

False |

Question 7 |

If the number of leaves in a tree is not a power of 2, then the tree is not a binary tree.

True | |

False |

In the above binary tree, no. of leaves is 3, which is not the power of 2. Hence the given statement is false.

Question 8 |

Regularity is preserved under the operation of string reversal.

True | |

False |