HALF-YEARLY EXAMINATIONS FEBRUARY

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1 HALF-YEARLY EXAMINATIONS FEBRUARY 2016 Subject: Computing Form: 4 Time: 1½ hrs MARKING SCHEME Computing Form 4 Half Yearly Exams 2016 Page 1

2 Section A Answer ALL questions. Each questions carries 5 marks. 1. Fill in with either True (T) or False (F). a) Tailor-made software has a very high initial cost. b) Off-the-shelf software contains many features, often more than you need. c) Off-the-shelf starts with the minimum necessary requirements and allows the user to add on later. d) All changes and feature requests of a tailor-made package are made free of charge. e) Tailor-made software can be designed to your exact business needs and processes. True True False False True 2. This question is about Binary Addition. a) Perform 8-bit Binary Addition for , showing your working below. 78 to Binary to Binary Addition = = [2] b) Show how -78 is stored in an 8-bit register using 2 s complement. Working space Answer: Computing Form 4 Half Yearly Exams 2016 Page 2

3 3. What do the following acronyms stand for? a) ATM: Automated Teller Machine b) CAD: Computer Aided Design c) CAM: Computer Aided Manufacturing d) CAL: Computer Aided Learning e) POS: Point Of Sale 4. The System Development Life Cycle consists of 7 stages. Number each stage to show their correct order. The first and last stage are already numbered. Present System Study and Analysis 2 System Maintenance 7 Implementation and Changeover methods 5 Project Selection and Feasibility Study 1 Programming and Documentation 4 Control and Review 6 Design of the new computerised system 3 5. a) Perform 2 s complement subtraction to show the result of to Binary -45 to Binary 2 s complement = = [2] b) In 2 s complement, what do all positive numbers have in common? They all start with a 0. Computing Form 4 Half Yearly Exams 2016 Page 3

4 6. State whether the following statements refer to Syntax (S), Logic (L) or Runtime (R) errors. a) Forgetting to close the curly bracket of a method in Java. S b) c) An unhandled exception is triggered while the program is running. Trying to declare and use a Scanner object without importing the Scanner class. R S d) A Java program outputs the wrong result when it is executed. L e) Typing System.out.println( Result = a+b ); in order to add the contents of a and b and output the result. L 7. Using Java syntax, write a single line statement to perform the following: a) Output the phrase Hello World! on screen and skip to the next line. System.out.println( Hello World! ); b) Declare a public class called Student. public class Student {} c) Declare a private attribute called name of type String. private String name; d) Declare an attribute called amount of type double. double amount; e) Declare and create an object called student1 of type Student. Student student1 = new Student(); 8. Identify whether each of the below is a method, attribute or constant in Java. a) public void setname(string name) {} method b) String surname; attribute c) public Student() {} method d) final int STUDENTS = 20; constant e) int students; attribute Computing Form 4 Half Yearly Exams 2016 Page 4

5 9. Fill in the blanks using one of the following: GPS, E-commerce, Online Banking, Computer Process Control, Simulation a) Doing business electronically over the Internet. E-commerce b) Is used in Anti-lock Braking Systems in cars. Computer Process Control c) A system that provides location information. GPS d) Online money transfer between accounts. Online Banking e) Modelling a real-life situation. Simulation 10. Convert between Binary, Decimal and Hexadecimal. The shaded cell implies that no conversion to binary is required. Binary Decimal Hexadecimal B3 [1, 1] C [1, 1] 79 4F space for working Computing Form 4 Half Yearly Exams 2016 Page 5

6 11. Write down the correct answer. a) The largest positive number in an 8-bit 2 s complement register. b) The largest positive number in an 8-bit unsigned register. c) The largest negative number in an 8-bit 2 s complement register. d) The smallest negative number in an 8-bit 2 s complement register e) The smallest number in an 8-bit unsigned register Software can be categorised as System Software or Application Software. a) What should be installed first, System or Application Software? System Software b) Is an Operating System considered as System or Application Software? System Software c) What do you understand by portable software? Software that can run on different computers without being installed. d) Mention one storage device normally used to store portable software. USB Pendrive Computing Form 4 Half Yearly Exams 2016 Page 6

7 Section B 13. Java is an object-oriented language. a) A simple database application is being developed for a local football club. The application includes a class called Player. Five attributes of this class are name, surname, height, shirtnumber and position. i) Show how you would declare each of the above attributes as private attributes. The first attribute is declared as a guideline. Attribute: name Declaration: private String name; surname private String surname; height private double height; shirtnumber private int shirtnumber; position private String position; ii) The Player class will contain a method called outputfullname(). When referenced, this method will output the full name of the player, which consists of the name followed by a space followed by the surname. The method should not skip a line after outputting the full name. Complete the method outputfullname() below: public void outputfullname() { } System.out. print ( name+ +surname ); [4] Computing Form 4 Half Yearly Exams 2016 Page 7

8 iii) A special method called setshirtnumber( ) needs to be implemented. This method: 1. Accepts a shirt number as a parameter. 2. Checks if the shirt number is between 1 and If the shirt number is not within the range, it will set it 0, otherwise it will set it to the parameter value passed. Complete the method setshirtnumber( ) below: public void setshirtnumber( int newshirtnumber ) { shirtnumber = newshirtnumber; if (_shirtnumber < 0 shirtnumber > 99 ) { shirtnumber = 0 ; [2] [2] } } b) For testing purposes, an object of type Player will be created in another main class of this application. The main class will be called Team. i) What is the method that identifies the main class called? the main method ii) Complete the main class below to create the Player object. public class Team { public static void main (String[] args) { [2] Player player1 = new Player() ; [2] } Computing Form 4 Half Yearly Exams 2016 Page 8

9 14. Systems Analysis involves a sequence steps in the creation and maintenance of a new or updated computer system. a) Who is in charge of the Systems Analysis process? The Systems Analyst b) A fact-finding exercise is conducted on the present system to determine how it currently works. Mention 3 methods that can be used to perform such an exercise. a) Observation b) Interview c) Questionnaires c) What important decision needs to be taken during the Feasilibity Study stage? Whether to proceed with the creation of the new system or not d) An essential part of a computerised system is Documentation. i) Besides User documentation, what other 2 types of documentation are prepared? a) Technical b) Program ii) Mention any 2 sections found in the User documentation. a) Installation b) Troubleshooting Computing Form 4 Half Yearly Exams 2016 Page 9

10 e) Four different changeover methods can be considered when implementing the new computerised system. Name and briefly describe 3 changeover methods. Changeover Method 1: Direct Changeover Description: Complete replacement of old with new Changeover Method 2: Parallel Changeover Description: Both systems working together until new system is steady and fully working Changeover Method 3: Pilot Study Description: Tested on a section and implemented on the rest if found to be working as it should f) What do you suggest to be the most feasible changeover for a bank? Give one reason for your answer. Changeover: Parallel Reason: Safest due to fallback system and money to implement it is not an issue g) Control and Review is a very important stage once the new system is implemented and functional. Mention 2 procedures which are performed at this stage. a) Find any discrepancies between proposed and actual system b) Set dates for any possible maintenance to be performed h) Why is System Maintenance important from time to time? Urgent updates are performed so that the system is always improved and will not be easily compromised Computing Form 4 Half Yearly Exams 2016 Page 10