451/1 COMPUTER STUDIES Paper 1 (THEORY) July/August 2012 2 hours WESTLANDS DISTRICT JOINT MOCK EXAMINATION Kenya Certificate of Secondary Education COMPUTER STUDIES Paper 1 (THEORY) 2 hours INSTRUCTIONS TO CANDIDATES This paper consists of TWO sections; A and B. Answer ALL the questions in section A. Answer question 16 and any other THREE questions from section B. All answers should be written in the spaces provided on the question paper. For Official Use SECTION QUESTIONS SCORE A 1-15 B 16 17 18 19 20 Total Marks
SECTION A (40 marks) 1. (a) The table below shows the records of four students NAME SEX CLASS FEE BALANC E Margaret F 3 2000 Paul M 3 6000 Sharon F 4 3000 Peter M 3 6000 Given the following logical expressions. If NOT (SEX = ‘F’) AND (CLASS = 4) AND ( FEE BALANCE = 3000 ) Indicate the result of the expression when applied on the record for Sharon. (1mk) - FALSE Award 1 mark for a correct answer. (b) a) Differentiate between a formula and a function as used in Excel (2marks) A formula is constituted / constructed by the user while a function is a ready to use formula that comes with the program . Award 2 marks for clear difference, one for each clearly defined term. 2. (a) Name two examples of flat-panel monitors available in market today other than Liquid crystal display. (2marks) EL – Electro Luminescent GPD – Gas Plasma Display Award 1 mark for each correct answer (b) Explain how the two technologies used in making LCD monitors work. (2marks) Passive matrix- LCDs create images by scanning entire screen. Active matrix- LCDs create images using the thin film transistor technology. Award 1 mark for each clearly explained answer, ½ mark for each correct answer without explanation 3. Briefly describe how the following data security measures function . (3mks) (i)Audit trail
Audit trail: A study to evaluate if a system is secure. Acts as a measure of preventing crimes from occurring (ii) Log files Log files: Records the activities taking place in a computerized system (iii) Firewalls Fire walls: Acts as a vetting system for remote request of information from a system. Award 1 mark for a clear description. 4. (a) Name any two methods that are commonly used in testing for errors in a program. (2mks) - Desk checking ( Dry- run ) - Using debugging utilities - Using test data. Award 1 mark for each method named (b) What is Prototyping as used in system development? (1mark) It is a Rapid system/program development technique where system developers quickly capture user requirements by designing system interfaces in the presence of the user. Award 1 mark for a clear definition. 5. Convert 842 10 to hexadecimal. (2mks) 16 842 10 A award marks as follows 16 52 4 - Division 1mk 16 3 3 - Correct answer 1mk 34 A 16 6. (a). What is a section break as used in word processing? (1 mks) - a section break marks the end and beginning of a section in a document Award 1 mark for a clear definition.
- Fall '19
- Award marks, Official Use