MRIEHEL SECONDARY SCHOOL HALF-YEARLY EXAMINATIONS 2016~17 Year 9 Computing Time: 1hr 30mins MARKING SCHEME 1. What do the following abbreviations stand for? Central Processing Unit a) CPU : Most Significant Bit b) MSB : Graphical User Interface c) GUI : Analogue to Digital Converter d) ADC : American Standard Code for Information Interchange e) ASCII : (5 marks) 2. A computer system can perform seven basic functions. a) Input is one of the seven functions of a computer system. Name the other six functions. Output Process Send Receive Save Retrieve (6 marks) Page 1 of 10
3. The following question is about computer systems. a) Using the following keywords, draw the basic block diagram of a computer system. Use arrows for data flow between one block and another. Input Devices Main Memory Output Devices Secondary Storage CPU Space for diagram CPU Input Devices Main Memory Output Devices Secondary Storage 1 mark for each correctly placed block (5 total) 1 mark for input/output lines 1 mark for CPU-MM lines 1 mark for MM-SS lines (8 marks) b) Use numbers from 1 to 4 to order the following types of computers according to their processing power. (Note: 1 refers to the most powerful and 4 refers to the least powerful). Microcomputer Supercomputer Minicomputer Mainframe 4 1 3 2 (4 marks) Page 2 of 10
4. Complete each row of the following table to show the same number in binary, decimal and hexadecimal. Please show your working in the space provided. Binary Hexadecimal Decimal 1 1 0 1 0 1 0 1 = D 5 = 213 1 0 1 1 0 1 1 0 = B 6 = 182 1 1 0 0 0 1 1 0 = C 6 = 198 Space for working: (6 marks) 5. State whether the following statements are True or False : True a) Hexadecimal is a convenient way to represent binary data. False b) One kilobyte is larger than one megabyte. False c) The Internet is just a part of the World Wide Web. False d) Application software manages the computer s hardware resources. (4 marks) Page 3 of 10
6. What is each of the following called? a) A group of 8 bits: Byte b) A number system that uses sixteen digits: Hexadecimal c) Where data is temporarily stored when we copy and paste: Clipboard d) Data that is processed, organized, and structured so that it becomes useful: Information e) A device which lets us transmit digital data over an analogue telephone line: Modem 7. Underline the correct answer in the brackets for each statement. a) The computer works using ( analogue digital ) signals. b) A speedometer is an example of ( an analogue a digital ) device. (5 marks) c) A telephone line can only allow the transmission of ( an analogue a digital ) signal. d) The number of students in a classroom is a ( continuous discrete ) quantity. e) Sound from a microphone needs to be converted to ( an analogue a digital ) signal before being used by a computer. 8. This question is about image representation (5 marks) a) Mark with a each of the following statements as being either raster or vector. Raster Vector a. b. c. d. Is the ideal type of image for storing someone s photo. Can be enlarged or reduced without affecting the quality of the image. Quality of the image depends on the resolution used. Images which are drawn using lines, text, and shapes. (4 marks) Page 4 of 10
9. This question is about Logic Circuits. a) Write the name of the Logic Gates under the symbols shown below: OR (3 marks) b) Fill in the blanks: AND i. The gate gives 1 as an output only if both inputs are 1. NOT ii. The gate is represented by the Boolean expression X = Ā. OR AND NOT iii. The gate gives 1 as an output if at least one of its inputs is 1. c) Consider the logic circuit below: (3 marks) i. What type of logic gate is represented by the circle labelled G1? NOT GATE ii. Complete the following truth table for the logic circuit above. A B C D E F 0 0 0 1 0 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 1 1 1 1 1 0 0 0 0 0 1 0 1 0 0 0 1 1 0 0 0 0 1 1 1 0 1 1 Page 5 of 10 (3 marks)
10. This question is about application and system software a) Use arrows to match the following tasks with the most appropriate programme. The first one has been done for you. Task required To write a letter to a friend To do research on the Internet To calculate expenses To create a greeting card Program to use Spreadsheet Software Graphics Software Word Processor Web Browser (3 marks) b) For each description below, mention the utility/action that carries it out. Defragment Scandisk Compression Antivirus Format a. b. c. d. e. Rearranges the file and free space on your disk making files faster to access. Protects your computer from malicious programmes. Reduces the size of files stored on the computer. Prepares a disk for use and makes it capable of accepting data. Checks your storage device for any errors on their file system. Defragment Antivirus Compression Format Scandisk (5 marks) c) Mention two features of an operating system? Provides User Interface, accepts inputs, sends Feature 1 : outputs, recognizes peripheral devices, manages files and folders, loads and runs applications, Feature 2 : manages system resources, provides clipboard Page 6 of 10
11. This question is about character coding systems. a) Why is it necessary to have a standard character coding system like ASCII? To enable the exchange of information between computers. b) If the character A has an ASCII code of 65, which code number represents the character K? 75 c) Standard ASCII is a 7 bit character set. Therefore how many characters can it represent? 2 7 or 128 d) Mention another character coding system that can be used to represent many more characters than ASCII. UNICODE (4 marks) 12. The following questions are about Main Memory a) List two differences between RAM and ROM RAM Volatile Writeable ROM Non-Volatile Read Only b) Mention one use of RAM in a computer system. The RAM stores the instructions and data which Use of RAM: require fast access by the CPU. c) Mention one use of ROM in a computer system. The ROM stores the program required to start up Use of ROM: the computer, this program is called the BIOS. Page 7 of 10
13. The following questions are about Email. a) What is written in the Carbon Copy field? Tick ( ) the correct statement below. i. An email address of a person ii. An address of a web site iii. A copy of the email message b) Mention two advantage of email over a regular postal service. Messages by email are delivered faster than Advantage 1: with regular postal service. Sending email is cheaper and more environment Advantage 2: friendly than sending regular mail. 14. This question is about Word Processing a) Explain what each of the following Word features does. This language feature helps to search and Spell Check : correct spelling mistakes. This feature helps you find occurrences of a Find and Replace : word and replaces it with another word. Header is the text that appears at the top Header and Footer : of each page. Footer appears at the bottom. (3 marks) b) What is Mail Merge used for? Give an example. Mail merge allows us to create many personalised documents that have the same format but contain personalised data or information such as mailing labels or personalised letters. Page 8 of 10
15. The screenshot below shows part of a spreadsheet used to collect ticket sale data. a) From the screenshot above, write down the function you would type in: =SUM(B2:B6) i. cell B7: =AVERAGE(B2:B6) ii. cell B8: b) Why is the use of formulas and functions preferred over working results manually? Because results are calculated faster, more reliably, and if data is changed the results are recalculated automatically. c) Mention two other advantages of Spreadsheets. Data can be easily edited. i. Advantage 1: Charts can be created easily. ii. Advantage 2: 16. Fill in the following statements about the Internet a) Briefly describe what is a search engine. A search engine is a website that enables users to find information on the World Wide Web. b) Briefly describe what a URL is used for. A URL is used to provide the location of documents and other resources on the World Wide Web. Page 9 of 10
17. Explain the difference between the following terms: a) Input and Output Data that is sent into the computer to be processed is considered an input. Any information that is sent out from the computer is considered an output. b) Hardware and Software Hardware refers to the physical parts of the computer which you can touch while software refers to the data and instructions given to the computer to carry out tasks. c) Data and Information Data is raw, unorganized facts that need to be processed while information is data which is processed, organized, structured so as to make it useful. d) Application Software and System Software Application software allows the computer to perform useful tasks required by the user while system software allows the user to manage and maintain the computer system. e) Internet and World Wide Web The Internet is a global, interconnected network of computer devices while the World Wide Web is the part of the Internet related to websites and web browsing. END OF EXAMINATION PAPER Page 10 of 10