IT &computer MCQ section 4 MCQ Questions & Answers Detailed Explanation

Answer: (b)

In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer. Devices that operate at the physical layer include repeaters, hubs, network interface cards (NICs), cables and connectors. Repeaters are used to regenerate electrical signals that have attenuated (i.e., weakened) as a result of distance.

Answer: (a)

The size of a display is usually by monitor manufacturers given by the diagonal, i.e. the distance between two opposite screen corners. This method of measurement is inherited from the method used for the first generation of CRT television when picture tubes with circular faces were in common use.

Being circular, only their diameter was needed to describe their size. Since these circular tubes were used to display rectangular images, the diagonal measurement of the rectangle was equivalent to the diameter of the tube’s face.

Answer: (c)

A hierarchical database model is a data model in which the data is organized into a tree-like structure. The structure allows representing information using parent/child relationships: each parent can have many children, but each child has only one parent.

Answer: (d)

A bit (a contraction of binary digit) is the basic capacity of information in computing and telecommunications; a bit can have the value of either 1 or 0 (one or zero) only.

These attributes may be implemented, in a variety of systems, by means of a two-state device.