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

Answer: (b)

The computer mouse as we know it today was invented and developed by Douglas Englebart during the 1960’s. While creating the mouse, Douglas was working at the Stanford Research Institute and originally referred to the mouse as a “X-Y Position Indicator for a Display System.” This mouse was first used with the Xerox Alto computer system in 1973.

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.