Chapter 2 Understanding functions and operations of various ICT

A. Multiple Choice 
 1. A
 2.
 3. B
 4. B
 5. E
 6. E
 7. C
 8. B
 9. A
10. C

B. Essay

1. In ASCII code, by what code is letter W represented ?
2. Name and explain all supporting devices inside a CPU ?
3. What is abbreviation and the function of Rom ?
4. Name three examples of network interface cards.
5. Name and explain several cables that use on a wired network.

Answer :

1. the letter W is represented by the number code 87
2. a. Control unit is to translate commands or instructions in a series and then continues them to the entire computer parts.
    b. Arithmetic logic unit (ALU) is to process data by adding, substracting,comparing and using logical formulas.
    c. Memory isto collect or to store data to run an application program.
3. Rom (read only memory) is a permanent memory that can be read but cannot be updated. Rom is to save computer operation program, such as BIOS and booting.
4. 1) Ethernet
    2) Arcnet
    3) Token ring
5. a) UTP Cable (Unshielded Twisted Pair)
        It consists of a pair of plastic wrapped conductor and each is colored. The frequency ranges from 100 Hz to 5 MHz.
    b) STP Cable (Shielded Twisted Pair)
        STP cable is similar with UTP cable, except that it has double wrap. STP cable connector and UTP cable connector are alike.
    c) Coaxial Cable 
        Coaxial cable consists of a main copper conductor with three wraps. The first and third are plastic wraps. The first and third conductor are isolator, while the second wrap in the middle is a conductor.
    d) Optical Fiber
         Optical fiber is made of plastic or glass that acts as a medium for signal transmission in the form of light. connector for the optical fiber is an FO connector. The optical fiber is fragile and therfore difficult to be moved and installed, needs an expensive maintenance, and the cost of the optical fiber is relatively expensive.