MSHS 2020 Computing P1

Class/ Index Number / Centre Number/ ‘O’ Level Index Number / Name MARIS STELLA HIGH SCHOOL PRELIMINARY EXAMINATIONS SECONDARY FOUR COMPUTING 7155 Paper 1 Written 26 August 2020 2 hours Candidates answer on the Question Paper No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your class, index number and name in the spaces at the top of this page. Write in dark blue or black pen. You may use a HB pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Approved calculators are allowed. Answer all the 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. For Examiner’s Use This document consists of 13 printed pages. 80

2 1 Draw a line between the description and the correct spreadsheet function. Description Function CEILING Returns the kth largest number in range RAND Returns the largest number out of the numbers in the given range or cell references RANDBETWEEN Returns a random number greater than or equal to zero and less than one HLOOKUP Rounds up a number to an exact number of significance LARGE Search for data in a row and returns associated data in the same column. MAX [5] 2 (a) A sports event company uses a digital camera attached to a drone to video their events from the sky. The video is stored as it is captured, on a device that is attached to the drone. Circle the most suitable type of media to store the video. (i) Optical Magnetic Solid State [1] (ii) Give two reasons to justify your choice. 1 ……………………………………………………………………………………….. …………………………………………………………………………………………. 2 ……………………………………………………………………………………….. …………………………………………………………………………………………. [2]

3 3 Insert three of the following words about different types of software in the correct place in each scenario below. public domain software proprietary software open courseware shareware freeware (a) Ali’s company requires productivity software that can be used in his business for emailing customers, creating orders, and tracking of the company’s profits and losses. He would also like regular customer support and updates from the software company that owns the source code of the software. The most suitable category of software for this usage is …………………………… (b) Mingxuan wants to learn more about Python programming during the school holidays. He wants to enrol for free online lessons provided by a university’s website that contains videos and training materials for his learning. The most suitable category of software for this usage is …………………………… (c) Sharon wants to purchase accounting software for her company’s use. She wants to try out a few features of the software before making a decision whether to purchase the full version. The most suitable category of software for this usage is …………………………… [3] 4 Five statements about interpreters and compilers are shown in the table below. Tick ( ü ) to show whether the statement refers to an interpreter or to a compiler. Statement Interpreter Compiler Translates the entire program in one go. Takes one statement at a time and executes it. Program runs at a faster speed because translation was completed earlier. Stops the translation process as soon as the first error is encountered. Syntax errors are detected before program runs. [5]

4 5 (a) Convert the positive whole denary number 388 into a 12-bit binary number. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [2] (b) Convert this binary pattern into hexadecimal. 1 0 1 1 0 0 1 0 1 0 0 1 0 1 1 0 ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [2] (c) RGB codes are one example of where hexadecimal numbers are preferred to binary numbers. Give two reasons to explain so. ………………………………………………………………………………………………. ………………………………………………………………………………………………. ………………………………………………………………………………………………. ………………………………………………………………………………………………. [2] (d) State another two ways in which hexadecimal numbers are used to represent data. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [2]

5 6 Complete the following paragraphs by filling in the missing words about networks. A ……………………………….. is a network of computing devices connected within a small geographical area, typically within the same building, such as in an office. A ……………………………….. is a network of computing devices covering across multiple geographical locations, such as those between a main office in a country and branch offices in other countries. In an office, there would typically be many ……………………………….. computers that initiate connections to request for resources and services from a centralised computer to perform operations. This computer which fulfils these requests is known as a ……………………………….. as it centrally manages resources and services. This type of network is more ……………………………….. than a peer-to-peer network as access rights are centrally controlled. [5] 7 A program asks the user for a string and prints out the string in reverse order. For example, “Computing” returns a result of “gnitupmoC”. For each test case condition below, write down one expected input and one expected output. Test Case 1 for Normal Conditions Expected Input Expected Output Test Case 2 for Boundary Conditions Expected Input Expected Output Test Case 3 for Erroneous Conditions Expected Input Expected Output [6]

6 8 Personal information needs to be kept safe from unauthorised access. Explain how the following industries verify personal information. For each industry, identify the authentication method and explain how it is implemented to verify user identity. (a) Online banking services by banks (i) Authentication Method: …………………………………………………………… [1] (ii) How it is implemented: …………………………………………………………… ………………………………………………………………………………............. ………………………………………………………………………………............. ………………………………………………………………………………............. [2] (b) Passport checking by Immigrations Department (i) Authentication Method: …………………………………………………………… [1] (ii) How it is implemented: ……………………………………………………………. ………………………………………………………………………………............. ………………………………………………………………………………............. ………………………………………………………………………………............. [2] (c) Explain two ways in which a user can protect against unauthorised access of personal information when using social networking websites. ………………………………………………………………………………....................... ………………………………………………………………………………....................... ………………………………………………………………………………....................... ………………………………………………………………………………....................... [2] 9 A computer has both an IP address as well as a MAC address. (a) Explain what an IP address is and its function. ……………………………………………………………………………………… ……………………………………………………………………………………… [2] (b) Explain what a MAC address is and its function. ……………………………………………………………………………………… ……………………………………………………………………………………… [2]

7 10 The spreadsheet below contains information about students who registered at a running club. The ID field is a text that consists of the gender (first character), year of birth (second to fifth character) and member number (last three characters). Columns C and D are displayed using data in column B. (a) Identify the most appropriate data type for the follow