BVSS 2019 P1

Name: ________________________________ ( ) Class: __________________ COMPUTING 7155/01 2 September 2019 PAPER 1 Written 2 hours Candidates answer on the Question Paper. No Additional Materials are required. ------------------------------------------------------------------------------------------------------------------------------------ READ THESE INSTRUCTIONS FIRST Write your Name, Register Number and Class on the top of this page. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. No marks will be awarded for using brand names of software packages or hardware. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. You should show all your working. Setter: Mr Low Chee Wah Parent’s signature : __________________ This question paper consists of 16 printed pages. 80 BUKIT VIEW SECONDARY SCHOOL PRELIMINARY EXAMINATION Secondary 4 Express BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL

2 1. A company uses spreadsheet software. Match each description to the correct spreadsheet function. [4] Description Returns number rounded up to an exact multiple of significance. l Returns the future value of a loan given the interest rate, number of periods and the present value. l Returns the number of non-empty cells in the given range references. l Returns the interest payment in the specified period for a loan of the present value with an interest rate over the number of periods. l Function l Ceiling l Counta l Count l Floor l FV l IPMT l PPMT l PV l Round

3 2. (a) Convert the binary number 1010 1011 into a denary number. Show your working. ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………[2] (b) Convert the hexdecimal number AE3 into a denary number. Show your working. ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………[2] (c) Convert the denary number 123587 into a hexadecimal number. Show your working. ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………[2] (d) List two uses of hexadecimal notation in computer science, other than ASCII. (i) ……………………………….……………………………………… ……………………………………………………………………….. ……………………………………………………………………….. (ii) ………………………………………………….……………………… ……………………………………………………………………….. …………………………………………………………..…………. [2]

4 3. Fill in the blanks with the correct word(s) from the following list. address bus arithmetic logic unit control unit central processing unit data bus floppy disk memory process register primary storage RAM ROM secondary storage A(n) ……………………… transfers required memory location from processor to memory. It is uni-directional. The ……………………… is part of the processor that follows instructions and decides when data should be stored, received or transmitted by different parts of the computer. ……………………… processes data by performing basic mathematical and logical operations. ……………………… is where large amounts of data are stored, such as in a hard disk or hard drive. ……………………… is where data and instructions are stored temporarily so that they can be quickly accessed by the processor when needed. [5]

5 4. (a) Parity checks are used to detect errors in data transmission. In the table below, the received bytes were transmitted using odd parity. Tick to show whether each byte has been corrupted or not corrupted during transmission and state the reason. [3] (b) State one way in which the above error(s) can be corrected. ………………………………………………………………………………… ….……………………………………………………………………………[1] Received byte Corrupted Not corrupted Reason 10001101 01101101

6 5. With the rise of the Internet and the usage of online platforms, cybersecurity is becoming more important. Two-factor authentication is one of the safety measures that online banking, government-linked and e-commerce websites are adopting. (a) Spyware and Trojan horse are examples of cybersecurity threats. Explain what is meant by each of these terms and how they can be used in cyberattacks. (i) Spyware: …………………….……………………………………… ……………………………………………………………………….. ……………………………………………………………………….. ……………………………………………………………………….. (ii) Trojan horse: ……………………………….……………………… ……………………………………………………………………….. ……………………………………………………………………….. …………………………………………………………..…………. [4] (b) Explain what is meant by two-factor authentication and state an example of what is needed in this process. Two-factor authentication: ……………………………………………... .…………………………………………………………………………….. ………………………………………………………..…………………….. Example: ………………………….…….………………………………… …………………………………………………………………….……... [2]

7 6. Programming languages either uses an interpreter or a compiler. Python and Scratch are programming languages that typically use an interpreter, whereas C and Pascal are examples of programming languages that use a compiler. (a) What is an interpreter? ………………………………………………………………………………. …………………………………………………………………………… [1] (b) What is a compiler? ………………………………………………………………………………. …………………………………………………………………………… [1] (c) Johnny is thinking of picking up programming. Describe the advantage of using a programming language that uses either an interpreter or a compiler to help Johnny’s decision. (i) Advantage of using interpreter. ……………………………………………………………………….. ………………………………………………………….……………. (ii) Advantage of using compiler. ………………………………………………………….…….……… ……………………………………………………………………. [2] (d) Explain the computing term “Graphical user interface.” ………………………………………………………………….…………… ………………………………………………………………………………. …………………………………………………………………………… [1]

8 7. A topology describes the physical layout of a network. Understanding the topology is essential to designing a network. Tom needs to build a computer network for his company of 40 staff. (a) Suggest the type of topology for the computer network that is most suitable for Tom’s company. ………………………………………………………………………… [1] (b) Describe two advantages of this kind of topology. (i) ………………………………………………………………….... …………………………………………………………………… …………………………………………………………………… (ii) ………………………………………………………………….... …………………………………………………………………… …………………………………………………………………… [2] (c) Describe one disadvantage of this kind of topology. …………………………………………………………………………. ………………………………………………………………………….. [1] (d) Which network topology is the least reliable in