Computer Studies Paper 1 Questions and Answers - BSJE Mock Exams 2023

• This paper consists of two sections A and B.
• Answer ALL questions in section A.
• Answer question 16 and any other THREE questions from section B.

1. Give two reasons why smaller computers like Laptops tend to be more expensive than Desktop computers.       (2 marks)
2.  
   1. State two keyboard keys that work in a state of On/Off switches in operation                  (1 mark)
   2. State four factors you would consider when choosing a secondary storage device           (2 marks)
3.  
   1. What is distributed data processing?                      (1 mark)
   2. Outline two advantages of distributed data processing in an organization                      (2marks)
4. Differentiate between graphic-based and layout based desktop publishing software.         (2 marks)
5.  
   1. Write the following acronyms in full as used in operating systems.
      1. GUI (½ mark)
      2. WIMP (½ mark)
   2. State two factors considered when choosing an operating system for use in a computer. (2 marks)
6.  
   1. Define the term audit trail                                                                                                    (1 mark)
   2. List any three ways of recovering data lost through accidental erasure.                               (3marks)
7. State three functions of an email software.                                                                                (3marks)
8. Name two responsibilities that are carried out by a computer programmer                             (2 marks)
9. State three ways in which ICT can improve the access of News in Kenya.                         (3marks)
10. Give three reasons why people prefer in-house developed application programs to general-purpose application packages. (3marks)   
11. State any two negative impacts of ICT on the environment                              (2 marks)
12. Highlight three reasons why most network technicians prefer using command line operating systems to configure networking equipment.                    (3 marks)
13. A computer teacher wants to minimize illegal entry of people to a computer laboratory. Explain three measures which have to be put in place in order to curb this illegal entry.                             (3 marks)
14. Outline two benefits of mail merging.                 (2 marks)
15. Without proper marketing, a business cannot survive in a competitive environment hence computers are being used in a number of ways to enhance marketing. List any two ways of ensuring this is effected.                             (2 marks)
    
                                                                             SECTION B: (60 MARKS)
                              Answer question 16 (compulsory) and any other THREE questions from this section.
16.  
    1. Study the flowchart below and answer the questions that follow.
                                                 
       1. State the name of the control structure shown in the flowchart.                            (1 mark)
       2. Assuming the user keys in 12 and 19 when prompted to enter the values for B and A respectively, determine the printed values of P, T, W and y.    (4 marks)
       3. Write the pseudo code that would be used in place of the flowchart.                              (6 marks)
    2. What is the difference between looping and selection? (2 marks)
    3. State any two advantages of low level languages.                                                                 (2 marks)
17.  
    1. The following are some of the phases in the systems development life cycle (SDLC): system analysis, system design, system implementation, system review and maintenance. State four activities that are carried out during the system implementation phase       (4 marks)       
    2. Give three reasons why system maintenance phase is necessary in SDLC                     (3 marks)
    3. State two instances where observation is not a viable method of gathering information during system analysis stage (2 marks)     
    4. Various considerations should be made during input and output design. State two considerations for each case (4 marks)             
    5. List two sources of computer viruses              (2 marks)
18.  
    1. Use twos complement to perform the following arithmetic operations
       1. 15₁₀ - 12₁₀                     (4marks)
       2. 10111₂ - 1011₂                    (4marks)
    2. 1011₂ is a ones complement binary representation of a number using four bits work out the likely positive equivalent in base 10.                    (2marks)
    3. Convert the decimal fraction 10.375₁₀ to its binary equivalent.                  (4marks) 
    4. Assuming the existence of base six, list the numbers that would be used in the number system.        (1mark)                 
19.  
    1.  
       1. Write the acronym DBMS in full.                     (1mark)
       2. State any three functions of a DBMS.                                (3marks)
    2. Indicate the type of cell reference depicted by the following.                     (3marks)
       1. H5
       2. H $ 5
       3. $H$5
    3. Mr. Maanzo is a teacher at Soyet High school and wishes to use Spreadsheet to process the marks obtained by his students during the term. The worksheet below shows the details used.
       

       A	B	C	D	E	F	G	H	I
       1	NAME	CAT-1	CAT-2	CATTOTAL	EXAM	TOTAL	GRADE	PST
       2	Susan Muani	14	06		56
       3	Peter Kwena	13	08		34
       4	Mary Ann	10	04		59
       5	Paul Njeru	11	07		57
       6	Janet Frida	06	09		48
       7	Justin Gerard	08	07		50

       NB:CAT -1 and CAT -2 are out of 15 marks each and EXAM is out of 70 marks
       1. Write a function that displays “PASSED” when the total marks is >60 otherwise display “FAIL”.               (2marks)
       2. Write a function that assigns Paul P positions according to the total marks.                     (2mark)
    4. Use illustrations to explain two text alignment features used in electronic word processors      (4 marks)
20.  
    1. Match the following statements with repeater, router or a bridge.                (2 marks)
       

       STATEMENT	DEVICE
       Operates at data link layer
       Determine the best path for data to follow
       Regenerates signals
       Forwards everything which it doesn’t recognize

    2. Discuss two disadvantages of wireless networks.                      (4 marks)
    3. Write the following abbreviations in full.                 (2 marks)
       1. F.T.P
       2. H.T.T.P
    4. With the aid of a diagram, discuss Hybrid topology.                 (3 marks)
    5. State two advantages of using fiber optic cables.                   (2 marks)
    6. Explain the meaning of the following terms as used in signal transmission.        (2 marks)
       1. Attenuation
       2. Noise

                                                                            MARKING SCHEME

1. Give two reasons why smaller computers like Laptops tend to be more expensive than Desktop computers.            (2 marks)
   • Energy efficient
   • Portable                                                                                                                  First 2 x 1     
2.  
   1. State two keyboard keys that work in a state of On/Off switches in operation         (1 mark)
      • CAPS LOCK
      • NUM LOCK
      • SCROLL LOCK
      • INSERT                                                                                             First 2 x ½
   2. State four factors you would consider when choosing a secondary storage device    (2 marks)
      • availability of the device in the market
      • method of access
      • reliability
      • security
      • storage capacity
      • compatibility with existing computer
      • cost of the device                                                                    First 4 x ½
3.  
   1. What is distributed data processing?                      (1 mark)
      • Data processing technique where data processing is divided into groups physically located at different sites but connected to a central location.
   2. Outline two advantages of distributed data processing in an organization                   (2marks)
      • Errors easily corrected
      • Better reliability
      • Low cost
      • Enhanced security
      • System failure does not affect others
      • Encourages effective decision making
4. Differentiate between graphic-based and layout based desktop publishing software.  (2 marks)
   • Graphic based- They are specifically developed to edit and format graphic objects such as pictures and vector drawings.
   • Layout based- Are specifically developed to create different page layout designs for text and pictures.
5.  
   1. Write the following acronyms in full as used in operating systems.
      1. GUI - Graphical User Interface (½ mark)
      2. WIMP -   Windows, Icons, Menus and Pointers/ pointing devices. (½ mark)
   2. Factors considered when choosing an operating system for use in a computer. (2 marks)
      • The hardware configuration of the computer e.g. Memory Capacity, processor speed & hard disk capacity.
      • The application software intended for the computer.
      • The user friendliness
      • The documentation available
      • The cost of the operating system.
      • Reliability and security provided by the operating system.
      • The number of processors & hardware it can support.
      • The number of users it can support.
      • The type of computers in terms of size and make. For example some earlier Apple computers would not run Microsoft Operating System.                                                First 2x1
6.  
   1. Define the term audit trail                                  (1 mark)
      • Refers to careful study done on an information system by experts to identify any loophole that can be used to access the system                                                                     correct explanation award 1 mark 
   2. List any three ways of recovering data lost through accidental erasure.                       (3marks)
      • Recover from the recycle bin
      • Use undelete utilities in case of command line systems
      • Use the backup information
      • Use data recovery utility
      • Use the undo command to reverse the deletion action
7. State three functions of an email software.                                     (3marks)
   • Facilitates mail creation
   • Facilitates reading mails
   • Facilitates sending mails
   • Creating email accounts
   • Deleting mails                                                                                         first 3 x 1 mark
8. Name two responsibilities that are carried out by a computer programmer                   (2 marks)
   • Coding computer program using appropriate programming language.
   • Testing of programs for logical errors, syntax errors and semantic errors.
   • Debugging of programs.
   • Documenting programs i.e. program manuals.                                     first 2 x 1 mark
9. State three ways in which ICT can improve the access of News in Kenya.                         (3marks)
   • Through internet people are able to read even them out of the country
   • You tube people are able watch news
   • News alerts  eg messages
10. Give three reasons why people prefer in-house developed application programs to general-purpose application packages. (3marks)
    • The user gets a well tried & tested program, which he/she is able to use with confidence.
    • The user is able to quickly implement the results obtained from the use of the package.
    • Meets specific need of the user
    • Readily available documentation                                                            First 3 x 1 mark                                                   
11. State any two negative impacts of ICT on the environment                              (2 marks)
    • Computers consume a lot of energy and emit electromagnetic radiations
    • Dead computer parts and other accessories e.g. ink toner cartridges are disposed in landfills hence causing environmental pollution.
    • Exploitation of natural resources to produce electricity used to operate ICT devices    First 2 x 1 mark
12. Highlight three reasons why most network technicians prefer using command line operating systems to configure networking equipment.                    (3 marks) 
    • A CLI can be a lot faster and efficient than any other type of interface.
    • It is secure since the expert only knows the commands.
    • A CLI requires less memory to use in comparison to other interfaces.
    • A CLI doesn't require high graphics, hence a low-resolution monitor can be used.
    • A CLI does not require Windows to run  First 3 x 1 mark 
13. A computer teacher wants to minimize illegal entry of people to a computer laboratory. Explain three measures which have to be put in place in order to curb this illegal entry.           (3 marks)
    • Locking doors every time the room is not in use
    • Employ security guards at the entry points
    • Use cards that have unique number to open doors
    • Use biometric security eg. Speech recognition at the entry points       First 3 x 1 mark
14. Outline two benefits of mail merging.                     (2 marks)
    • Uniformity of letters
    • Faster production of letters
    • Accuracy of the content produced
    • There is backup
    • Saves on storage space since individual letters does not have to be stored     First 2 x 1 mark
15. Without proper marketing, a business cannot survive in a competitive environment hence computers are being used in a number of ways to enhance marketing. List any two ways of ensuring this is effected.                             (2 marks)
    • Electronic Commerce or e-business
    • Electronic presentation
    • Advertising                           First 2 x 1 mark
      
                                                                            SECTION B: (60 MARKS)
                                   Answer question 16 (compulsory) and any other THREE questions from this section.
16.  
    1. Study the flowchart below and answer the questions that follow.
       
       1. State the name of the control structure shown in the flowchart.                            (1 mark)
          • Selection                                                                                                  Award 1 mark 
       2. Assuming the user keys in 12 and 19 when prompted to enter the values for B and A respectively, determine the printed values of P, T, W and y.                                              (4 marks) 
          • P= 12, T= -7,W= 8, y = 19                                            Each correct value award 1
    2. What is the difference between looping and selection? (2 marks)
       • Looping executes the same block of code (module) again and again until a certain condition is fulfilled, while in selection, execution of a statement(I)depends on a condition that returns true or false ( yes / No)                                                              Well explained 2marks
    3. State any two advantages of low level languages.                                                                 (2 marks)
       • The CPU can easily understand machine language without translation.
       • The program instructions can be executed by the hardware (processor) much faster.
       • Allow direct control of each operation.
       • They require less memory space.
       • Low-level languages are stable, i.e., they do not crash once written                First 2 x 1 mark
17.  
    1. The following are some of the phases in the systems development life cycle (SDLC): system analysis, system design, system implementation, system review and maintenance. State four activities that are carried out during the system implementation phase                       (4 marks)        
       • system installation or deployment
       • staff training
       • file conversion
       • changeover strategies/plan                                                                             First 4 x 1 mark
    2. Give three reasons why system maintenance phase is necessary in SDLC             (3 marks) 
       • Enhance system efficiency for the changing functional environment & requirements.
       • To ensure User expectations are satisfied.
       • So that system adapts to new changes in the company’s organization.
       • To ensure system operation is based on the facilities of the current technological development.    First 3 x 1 mark
    3. State two instances where observation is not a viable method of gathering information during system analysis stage  (2 marks)
       • When system activities may take place at odd times causing a scheduling inconveniences for the analyst
       • When the information to be gathered is located over widely spread geographical areas  First 2 x 1 mark
    4. Various considerations should be made during input and output design. State two considerations for each case  (4 marks)
       

       Output Considerations	Input Considerations
       (i) Target audience: (ii) Frequency of report generation  (iii) Quality and format of information to be generated. (iv) Cost of producing the output (v) Mode of output & devices used for output, e.g., softcopy mode of output is produced through the screen.	(i) The contents & volume of input, and whether these contents can grow. (ii) The mode of input, the devices of input selected and their suitability. (iii) The format & sequence of input. (iv) The nature of the system, which determines the frequency of input, e.g., for Batch processing,

                                                                                                                                                    First 2 in each case  x 1 mark
    5. List two sources of computer viruses              (2 marks)
       • Contact with infected removable storage devices such as flash disks
       • Update of software through internet
       • Pirated software
       • Downloads from the internet                                                                              First 2 x 1 mark
18.  
    1. Use twos complement to perform the following arithmetic operations
       1. 15₁₀-12₁₀                     (4marks)
          15 => 11112
          12 => 11002
          -12 (2’s compliment) = NOT(11002) + 1
               = 0100₂
            1111
            0100      
           1 0011            (Ignore extra bit)
          = 0011₂
       2. 10111₂-1011₂                    (4marks)
          01011 (2’s compliment) = NOT(01011) + 1
                                               = 10101
            10111
            10101       
          1  01100            (Ignore extra bit)
          = 01100₂                 
    2.  1011₂ is a ones complement binary representation of a number using four bits work out the likely positive equivalent in base 10.                    (2marks)
       = NOT(011)
       = 100 => 410
    3. Convert the decimal fraction 10.37510 to its binary equivalent.                  (4marks) 
       10 => 1010        +       0.375 x 2 = 0.75
                                             0.75 x 2 = 1.50
                                              0.5 x 2 = 1.00
         1010  + 0.011 
         = 1010.011
    4. Assuming the existence of base six, list the numbers that would be used in the number system.           (1mark)
        0, 1, 2,3,4,5
19.  
    1.  
       1. Write the acronym DBMS in full.                     (1mark)
          • Database Management Systems
       2. State any three functions of a DBMS (3marks)
          • Keep data / store data
          • Process data
          • Analyse and output information 
          • Ensure security and integrity of data
          • Keep statistics of data items in a database                                                 First 3 x 1 mark
    2. Indicate the type of cell reference depicted by the following.                     (3marks)
       1. H5 – Relative Reference
       2. H $ 5 – Mixed Reference
       3. $H$5 – Absolute Reference                                                   Award each correct 1mark
    3. Mr. Maanzo is a teacher at Soyet High school and wishes to use Spreadsheet to process the marks obtained by his students during the term. The worksheet below shows the details used.
       

       A	B	C	D	E	F	G	H	I
       1	NAME	CAT-1	CAT-2	CATTOTAL	EXAM	TOTAL	GRADE	PST
       2	Susan Muani	14	06		56
       3	Peter Kwena	13	08		34
       4	Mary Ann	10	04		59
       5	Paul Njeru	11	07		57
       6	Janet Frida	06	09		48
       7	Justin Gerard	08	07		50

       NB:CAT -1 and CAT -2 are out of 15 marks each and EXAM is out of 70 marks
       1. Write a function that displays “PASSED” when the total marks is >60 otherwise display “FAIL”.              (2marks)
          =IF(G2>60, “PASSED”, “FAIL”)
       2. Write a function that assigns Paul Njeru positions according to the total marks.            (2marks)
          =RANK(G5,G2:G7,0)
    4. Use illustrations to explain two text alignment features used in electronic word processors          (4 marks)
20.  
    1. Match the following statements with repeater, router or a bridge.         (2 marks)
       

       STATEMENT	DEVICE
       Operates at data link layer	Bridge
       Determine the best path for data to follow	Router
       Regenerates signals	Repeater
       Forwards everything which it doesn’t recognize	Bridge

                                                                                                                                                   Each correct value award 1/2
    2. Discuss two disadvantages of wireless networks.                 (4 marks)
       1.  Difficult to establish or configure
       2. Initial cost is very high                                                               First 2 x 1 mark
    3.  Write the following abbreviations in full.                (2 marks)
       1.  F.T.P – File transfer protocal
       2. H.T.T.P – Hyper text transfer protocol                         Award each correct 1mark
    4. With the aid of a diagram, discuss Hybrid topology.                 (3 marks)
       This are groups of star – Configured networks connected to a linear bus backbone.
                             
    5. State two advantages of using fiber optic cables.                   (2 marks)
       1.  Noise resistance: It is immune to EMI.
       2. Less signal attenuation: signal can run for miles without requiring regeneration.
       3. Higher bandwidth: fibre optic cable can support dramatically higher bandwidths (and hence data rate) than all other cables.
       4. Smaller and lighter than copper cable hence space limited situations.
       5. Can be used in hazardous (highly flammable) places because they do not generate electrical signals.
    6. Explain the meaning of the following terms as used in signal transmission. (2 marks)
       1. Attenuation - It’s the loss of signal strength during transmission i.e. when an electromagnetic signal is transmitted along any medium, it gradually become weaker at greater distances;
       2. Noise - Random electrical signals that can be picked up by the transmission medium and result in degradation of the data.