BLSS Paper 1[Ans][Vetted]

BOON LAY SECONDARY SCHOOL PRELIMINARY EXAMINATION 2022 Name CCA Subject : COMPUTING Paper No : 1 Subject Code : 7155/01 Level : SECONDARY FOUR EXPRESS Date/Day : XX XXX 20XX / XXXXESDAY Time : XXXX – XXXX Duration : 2 HOURS Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Before you start your exam, check that you have received the correct paper and the number of printed pages are correct. Write your name, index number, and CCA in the spaces at the top of this page. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs or rough working. Do not use staples, paper clips, glue or correction fluid. Approved calculators are allowed. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. You should show all your working. The total number of marks for this paper is 80. This document consists of 13 printed pages.

2 BLS/PRELIM/2022/4E/COMP/7155/01 1 (a) A computer is a complex electronic device that utilizes many different components to perform calculations and output the desired results. (i) Buses are used to transfer data from one part of a computer to another. Draw one or more lines to match the type of bus (left) to their correct description(s) (right). Type of bus Description Transports information from memory to processor when reading data from memory Data bus Transports information from memory to processor when writing data to memory Transports information from processor to memory when reading data from memory Address bus Transports information from processor to memory when writing data to memory [2] (ii) What are the two components inside a CPU and what are their respective functions? Component 1 : Control Unit Function: Coordinates all input, output and data transfer functions in the computer …………………………………………………………………………………………………… ………………………………………………………………………………………………...[2] Component 2 : Arithmetic Logic Unit Function: Performs all logical and mathematical calculations …………………………………………………………………………………………………… ………………………………………………………………………………………………...[2]

3 BLS/PRELIM/2022/4E/COMP/7155/01 (b) RAM is placed near to the CPU as it is a “volatile” memory. (i) Explain the term “volatile” in this context. It means that data will be erased once the memory loses power. …………………………………………………………………………………………………… ………………………………………………………………………………………………...[1] (ii) State two functions of RAM. It stores data and programs that are frequently used. It stores temporary data or results from intermediate calculations. …………………………………………………………………………………………………… ………………………………………………………………………………………………...[2] (iii) Other than being volatile, state anothe