2021 SST S4 Computing Prelim P1 QP final

SECONDARY 4 PRELIMINARY EXAMINATION COMPUTING Paper 1 Written 7155/01 27 August 2021 (Friday) 2 hours CANDIDATE NAME CLASS INDEX NUMBER READ THESE INSTRUCTIONS FIRST Do not turn over the page until you are told to do so. Write your name, class, and index number in the spaces provided above. Write in dark blue or black pen. You may use a pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid/tape. 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 18 printed pages, including this Cover Page. For Examiner’s Use 1 8 2 3 3 6 4 6 5 4 6 10 7 6 8 14 9 9 10 6 11 8 Total /80

Page 2 of 18 1 (a) Computers use collections of wires called buses to transport data from one part of the computer to another. Draw one or more lines from each type of bus on the left to the description that applies to it on the 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] (b) Computers also require one or more hardware devices for input and output. (i) State what is meant by an input device. ……………………………………………………………………………… ……………………………………………………………………………… [1] (ii) Besides the mouse and keyboard, name two input devices that are required when making a video conference call on a computer. ……………………………………………………………………………… ……………………………………………………………………………… [2]

Page 3 of 18 [Turn over (c) The operating system of a computer is usually stored on its hard drive. However, its data and instructions are loaded into the random access memory (RAM) after booting up the computer. (i) Suggest why the operating system is not stored in the RAM. ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… [2] (ii) Explain why the operating system's data and instructions are loaded into the RAM instead of the read-only memory (ROM) after booting up the computer. ……………………………………………………………………………… ……………………………………………………………………………… [1] 2 IP and MAC addresses are used to identify individual computers so that data transmitted over a network can be directed to the correct destination. The table contains statements about IP and MAC addresses. Tick (ü) one or more boxes in each row to indicate if the statement is about IPv4, IPv6 or MAC addresses. Statement IPv4 Address IPv6 Address MAC Addre