COMPUTER Paper 1 Questions and Answers - KCSE 2022 Past Papers

Instructions to candidates

• This paper consists of two sections: A and B.
• Answer all the questions in section A
• Answer question 16 and any three questions from section B
• Candidates should answer the questions in English.

1. State the components of a computer system which performs each of the following tasks:
   1. Comparisons of numbers   (1 mark)
   2. Convert data into a computer format    (1 mark)
   3. Coordinate operations of an entire computer.  (1 mark)  '
2. Explain the term system files as used in opertaing system  (2 marks)
3. Explain the term label as used in a spreadsheet program.
4. Ahmed noted that some documents in his office computer were illegally accessed from other computers in his organization's network. State two control measures he should put in place to prevent further access.   ( 2 marks)
5. Figure 1 shows an extract from a spreadsheet program used by a shopkeeper to compute the total cost of items in stock.
   
   Write a function that would be used to obtain the total cost of cooking fat.   (2 marks)
6. Emmanuel inserted a textbox and types some text in it while workinig with a desktop publishing program. He realised that some of the text he had typed was not visible. State three ways in which he could make the text visible.   (3 marks)
7. Explain the term software documentation as used in systems development.     ( 2marks)
8. State three types of errors that may occur during computerised data processing.    (3 marks)
9. Mary has been employed as a Web Administrator in a media house. State three offical duties that she is likely to be assigned by her supervisor.      (3 marks)
10.  
    1. Explain the term time slice as used in computer data processing.     (2 marks)
    2. State two advantages of multiprocessing mode of data processing.     (2 marks)
11. State two differences between a transaction file and a report file as used in data processing.    (2 marks)
12. State three disk management activities that may be performed on a computer's hard disk during formatting operation.( marks)
13. The following is alist of computer output devices: 
    speaker, plotter, screen projector, touch screen, LCD, printer
    Categorise each of them as either softcopy output devices or hardcopy output devices.  (3 marks)
14. State three advantages of using a wireless computer keyboard.  (3 marks)
15.  State three types of objects that may be created in a database during the design stage. (3 marks)

SECTION B

Answer question 16 and any pther three questions from this section.

16.  
    1. State three advantages of machine programming languages.  ( 3 marks)
    2. Describe two types of translators as used in computer programming.  (4 marks)
    3. A financial institution would like to computerise its loaning processes. To ascertain the legibility of a borrower, the system should accept a customer's ID number and check whether the customer has previously defaulted the repayment of any loan. If the customer is reported to have defaulted, the message DEFAULTER is displayed, otherwise the amount of loan requested is granted. If the amount requested is greater than or equal to 1 million, a repayment of 6 years is displayed, if the amount is greater then 500,000 and less than 1 million, a repayment period of 3 years is dispplayed. Otherwise a repayment period of 1 year is displayed.
       Draw a flowchart to represent the logic of the computerised system.  (8 marks)
17.  
    1. With the aid of an example in each case, state one difference between a nibble and a byte as used in computer data representation.  (3 marks)
    2.  
       1. Convert the bimnary number 11101.101₂ to its decimal number equivalent.  ( 3 marks)
       2. Perform the following binary arithmetic operation using two's complement.   1110₂ − 1001₂   (2 marks)
    3. State two differences between BCD and EBCDIC as used in computer coding scheme.  ( 4 marks)
    4. Ann would like to use a smart phone to attend an online lesson, where a teacher is using video presentation. State three features that a smartphone must have for an effective online lesson.       (3 marks)
18.  
    1. Explain each of the following terms as used in Information and Communication Technology (ICT)
       1. Electronic Funds Transfer (EFT)   ( 2 marks)
       2. blogging  ( 2 marks)
       3. simulation ( 2 marks)
    2. Distinguish between pilot change over and parallel change over as used in system development.   ( 4 marks)
    3. Philip has developed a computerised system for a school and is currently in its implementaion stage.
       1. State three activities which he would carry out at this stage.    ( 3 marks)
       2. State two technical personnel who would be involved during this stage.   ( 2 marks)
19.  
    1.  
       1. State two differences between serial and parallel cables as used in computers.   ( 4 marks)
       2. Name four cables other than those in 19(a)(i) that are used to connect a computer with other devices.   ( 2 marks)
    2. Describe each of the following qualities of information:  
       1. Completeness  ( 2 marks)
       2. Timeliness  (2 marks)
    3. State the function of each of the following features in word processing:
       1. Word wrap  (1 mark)
       2. Sort  (1 mark0
       3. Indent  (1 mark)
    4. A hard disk of a computer was reported to have crashed. State two control measures that should have been put in place to prevent such an occurrence.   (2 marks)
20.  
    1. Explain the effect of each of the following occurrence in a computer network:
       1. A bi=us network topology with a missing terminator    (2 marks)
       2. A uni-directional ring network topology with one computer not operational (2 marks)
       3. A star network topology with a hub not operational  (2 marks)
    2. A school intends to connect their computer labs with the school administration block using a fibre optic cable. State three benefits that the school will realise from using the cable.   (3 marks)
    3. Explain each of the following terms as used in data security:
       1. recycle bin   (2 marks)
       2. patch   (2 marks)
       3. tapping  (2 marks)

MARKING SCHEME

SECTION A

1.  
   1. Comparison of Numbers
      •  Arithmetic logic unit
   2. Convert data into a computer digital format
      • Input device
   3. Coordinate operations of an entire computer
      • Control Unit
      • Operating system/system software
2. System files-they are files that contain information that is critical for th operation of a computer system.
3. Explanation of the term label in spreadsheets
   • A label is any text or alphanumeric characters entered a cell of a spreadsheet entry to describe content of a column or row
   • a name given to a cell /block /range of cells.
   • Entry that cannot be manipulated mathematically.
4. Measures required to prevent illegal access.
   • Installation of firewal
   • Change password
   • Data encryption
   • Antispyware/antimalware/antivirus
   • Enforce user level security
   • Use biometrics
   • Using a strong password to restrict access to the computer documents
   • Use log files to establish intruders who commit crime and be reprimanded/audit trail
   • Create awareness to the rules and regulations that govern the use of computers.   First 2 x 1=(2 marks)
5. Total cost function
   = Product (B2, C2)
   =product (B2:C2)
   =Product (B2*C2)
6. Ways of making text in a textbox visible in DTP
   • Resize the text box
   • Contrast the back-colour with the fore- colour
   • Create another textbox and link it to the one with text/autoflo
   • Use fitting features available in the DT program.
   • Resizing text
   • Change font style (bold/italics)           First 3 x 1=(3 marks)
7. Software documentation
   • It is a written text/instructions that accompanying computer software or embedded on a source code explaining how a software developed operates.
8. Types of errors during data processing
   • Transcription errors
   • misreading
   • Transposition errors
   • Computational errors
   • Algorithmic errors/logical/semantic   First 3 x 1=(3 marks)
9. Duties of a web administrator in a media house
   • Preparing media content
   • Uploading media content
   • Managing the content of the website
   • Managing website user's accounts
   • Ensuring security measures of the website           First 3 x 1 = (3 marks)
10.  
    1. Explanation of the term time slice
       • Time slice refers to the period which a job is allowed to run before the next job is processed in a time-sharing system 
    2. Advantages of multiprocessing mode of data processing
       • Enables efficient use of the process
       • The user is able to run more than one task hence saving on time
       • Increases reliability in the system
       • Enables efficient use of processor First 2 x 1 (2 marks)
11. Difference between transaction file and report file
    

    Transaction file	Report file
    - Its contents are temporary	- Contents are permanent
    - Its contents are used to update the master file	- Its contents are not used to update master file
    - Its content can't be used in decision making	- Its contents can be used in decision making

    First 2 pairs x 1 = (2 marks)
12. Operations performed on a disk during disk formatting
    • Delete existing partition
    • Assign drive letter
    • Make a drive to be primary partition
    • Insert drive labels
    • Extend partition of a drive
    • Create RAID volume
    • Create mirror volume
    • Merge partitions    First 3 x 1=(3 marks)
13.  
    1. Softcopy output devices
       • Speaker
       • Projector
       • LCD
       • Touch screen    4x½=(2 marks)
    2. Hardcopy output devices
       • Plotter
       • Printer   2x ½(1 mark)
14. Advantages of using a wireless computer keyboard
    • No loose cables which distract a user
    • Keying in can be done from a far distance
    • Reduces space requirement
    • Allows a user to operate a computer from safe position
    • It is portable
    • Easily be used by other devices    First 3 x 1=(3 marks)
15. Objects of database application programs
    • Table/file
    • Forms
    • Pages
    • Query
    • Module
    • Report
    • Macros   First 3 x 1=(3 marks)

SECTION A TOTAL - 40

SECTION B 

16.  
    1. Advantages of machine programming languages
       • They do not occupy a lot of memory space
       • They are executed at a faster speed
       • They do not require a translator
       • Any other
       • Hardly crush/stable   First 3x1=(3 marks)
    2. Types of translators in programming
       1. Assembler
          • It is used to translate programs in assembly language programs into computer understandable before execution.
       2. Interpreter
          • It is used for translating a source code program line by line while the CPU executes the translate line before going to be next one.
          • Translating high level language
       3. Compiler
          
          • It is used for translating the entire source code into object then the CPU executes it. The program goes through the linking process to join the program to all other files.
          • Translating high level language.
            First 2 x 2 =(4 marks)
    3.   
       
       Logic of the dsign 
       Total = 8 marks
17.  
    1.  
       • A nibble is made up of 4 bits e.g 1101 where as a byte is made of 8 bits, e,g 00001101
       • A nibble represents a hexadecimal digit whereas a mbyte canrepresent two hexadecimal numbers  
         Difference @2
         examples @½×2 =1
    2.  
       1. Convert 11101.101₂ to decimal number
          
       2. 1110₂ − 1001₂
          
    3. Difference between BCD and EBCDIC
       

       BCD	EBCDIC
       - uses 4-bits  - has no zone bits  - Mostly used in simple electronic devices  - Represents numeric data only  - Represents 24 i.e 16 characters	- Uses 8-bits  - has 4 zone bits  - Used in computers  - Represents alphanumeric data  - Represent 28 i.e 256  charcters

       2 x 2=(4 marks)
    4. Smartphone features to enable video conferencing/lessons
       • Camera
       • Microphone
       • Speakers
       • Application that supports video communication
       • High-capacity memory/adequate / enough memory           Any 3x1-(3 marks)
18.  
    1.  
       1. Electronic funds transfer- It is a term that refers to the means of electronically transferring money from one banking institution to another/financial institution to another          @ 2 marks
       2. Blogging is the process of creating information in a communication platform in order to disseminate/share with other users of the same platform in a communication platform      @2 mark
       3. Simulation - Use of multimedia / ICT to mimic real life activities.      @ 2 marks
    2. Difference between pilot and parallel system change-over
       • In pilot the new system is introduced in a branch or a section of-jo the organization and tested to ascertain its effectiveness whereas in parallel the system runs together with the old one concurrently, the two are compared until one is satisfied with the performanc of the new system, the old system is terminated.
         @ 4 marks
         (If any one definition or description award 2 marks)
         (Correct distinction award 4 marks)
    3. Activities carried out during implementation stage
       • Installing of new system
       • Training of users
       • Data transfer from the old system/data file conversio
       • routine maintenance
       • evaluation of the new system     Any 3x1 (3 marks)     
    4. Personnel involved in system implementation
       • The users/operators/technician
       • Data entry clerks
       • System analysts
       • Programmers
       • Trainers       Any 21-(2 marks)
19.  
    1.  
       1. Differences between a serial cable and a parallel cable
          

          Serial	Parallel
          - Less number of pins  - Used for long distnace communication  - Slow  -Less prone to error  -Transmit on bit at a time	- More pins  - Use for short distance communicaton  - Faster  - Prone to error  - Transmits 8 bits at a time.

       2.  Other cables
          • USB
          • VGA
          • PS/2
          • HDMI
          • Power cables
          • Patch cables
          • SCSI
          • Fire wire
          • Audio
            Any 4 x ½ = (2 marks)
    2. Qualities of information
       1. Completeness
          • Information should contain mall facts that are necessary for decision making
       2. Timelines
          • Information should be delivered at the right  place and the right time. 
            2 x 2 = (4 marks)
    3.  
       1. Word wrap - It is a feature that makes a word to automatically start on a new line if it does not fit at the end of the current line
          @ 1 mark
       2. Sort - a feature used in arranging a set of elements/ items in a predefines order  @ 1 mark
       3. Indent - A feature used to increase or decrease the distance of a paragraph/ line from left to right margin.   @ 1 mark
    4. Protecting a hard disk from crashing
       • Connecting the computer to a UPS system
       • disable unnecessary programs running in the background.
       • perform disk maintenance operation.
       • Installing an update antivirus.
       • Frequently blowing away dust in computer
       • Always shutting down the computer using the right procedure
       • Avoid dropping the hard disk
       • Not exposing it to strong magnetic field
       • Not exposing it to heat
       • Not exposing it to moisture    Any 2 x 1-2 marks
20.  
    1.  
       1. Bus network topology with a missing terminator
          • Terminators missing leads to clogging of the bus by data packets that do not reach the destination.
          • Slow down the speed of transmission.
       2. Uni-directional ring network
          • One adjacent computer to the failed node will not send but may receive.
          • Communication will not take place
       3. Star network topology with a hub not operational
          • The whole network will be down. 
          • Communication will not take place.   3x2 = (6 marks)
    2. Benefits of using fibre optic
       • Would be able to transfer large file
       • Less interference between the two sites
       • Faster transmission speed
       • Cable not prone to theft
       • Difficult to tap leaves droppig       Any 3 x 1-(3 marks)
    3.  
       1. Recycle bin
          • This is a folder which stores deleted files and folders from a omputer.
          • The files or folders can be restored to their original locat on or emptied completely from the folder.  @ 2 marks
       2. Patch
          • It is a file with a line of code used to repair a defect within a software without interrupting its proper operations. 
            @ 2 marks
       3. Tapping
          • This term refers to unauthorized access to information or data that is on its way from the host computer to the destination computer.
            @ 2 marks