admin@kcseforecast.com

Q&A-KCSE Computer Studies Paper 1

Define disk formatting and state three reasons for formatting a disk

Definition

  • Disk formatting is the process of preparing a data storage media for initial use

Reasons:

  • To make a disk blank for reuse
  • To make it compatible with another operating system
  • to create tracks and sectors for first time use

Describe one task that is commonly undertaken during the first phase of system development life cycle

  • The preparation of a system proposal which lists the problem definition, objectives of the study, terms of reference of study, constraints, and expected benefits of the new system, in light of the user requirements

Describe the following features of a graphical user interface:

(a) Pointer

(b) Desktop

(a) Pointer

  •  A graphical object on a computer screen that responds to move movement and allows the computer user to select and execute commands in graphical user interface operating systems

(b) Desktop

  • It Is a special folder in the file system that is displayed when no other windows are open

For your item named in (a) describe two different tasks that the microprocessor performs.

  • camera film speed, position (end of film), distance, light
  • washing machine amount of water, speed of wash/temperature/time
  • fridge temperature, display panel
  • air conditioning temperature, timing, display pane

State the type of software that is needed for logging onto the Internet and finding websites selling goods and services.

  1. logging on
  2. finding websites

logging on

  •  dial-up/communications software/ISPsoftware

finding websites

  •  browser/search engine


Interfaces enable computer users to interact with the operating system. State three advantages of using a graphical user interface (GUI) for loading programs and files.

  • novice can use the system right away
  • user-friendly/easy to select
  • click on icons/picture to select
  • easier to input/words are replaced with icons
  • no need to know command language to use the system/remember
  • command language
  • selecting item using mouse is faster than entering commands
  • avoids typing errors
  • no need to type
  • no need to remember commands
  • no need know the different commands for the different software
  • multitasking (several programs open at the same time therefore easier
  • /faster to switch
  • easier/faster switching between files, folders etc.

Computer programs require translation to execute. (a) Compilers and interpreters translate high-level programming languages into machine code. Describe the main differences between a compiler and an interpreter.

  • A compiler translates the whole program in one go whereas An interpreter translates each line of code (often an intermediate code) at run time
  • A compiler produces an executable file that will run on the target hardware machine without the compiler being installed  A run time interpreter will be required at run time
  • Compilers tend to be large complex programs Interpreters are smaller simpler programs
  • Interpreted programs can be amended and run without translating whole program Compiled programs have to be re-compiled after a change
  • Compilers compile programs that will usually only run on the target platform (hardware/operating system)  Interpreters will interpret same program (or intermediate code) on different (some virtual) platforms

Describe four features of the operating system when providing a graphical user interface on a personal computer. Give a suitable example of each feature.

  • Windows for example a word processing application and a spreadsheet
  • Menus, for example, allow the user to perform operations or run applications such as right-click to create a new folder  
  • Icons for example a picture of linked computers for networking
  • Pointers(mouse or touchscreen)  for example to select items/trigger events  
  • Shortcuts for example to frequently used applications for example having a shortcut to your mail client on your desktop
  • File navigation for example when searching the hard disc for a file/folder using a browser
  • copying / deleting / moving/sorting/naming/searching of files or folders for example copying of a file from the hard drive to a USB pen drive (File handling)
  • Desktop customisation for example changing the colours and background image
  • Copy and paste for example between applications e.g. copying a graph from a spreadsheet to a word processor
  • Error messages for example provide users with error/warning/help messages for example ‘printer out of paper’ 

State and explain characteristics of an algorithm

Input : An algorithm can take 0 or more inputs well defined outputs

Finiteness: an algorithm must terminate in finite time and after finite number of steps. 

Definiteness : an algorithm must be clear and unambiguous. Each and every step of an algorithm must be clear and precise and it must have only one meaning

Feasibility: should be feasible with the available resources

 

Output : must produce at least one well defined output

Independent : should have a step-by-step directions which is independent of any programming language

Correctness: should solve the problem it is designed to solve

Efficiency: must take the shortest time possible to run and should require the least memory space. It should use a minimum number of computation steps and memory to produce the desired  output. takes little time and memory to run

Generality: should not be limited to a specific case. It should work for all the valid inputs. works for many possible inputs

Effectiveness : should statements that are relevant to the problem. Every step must be basic and essential. 

 

State the characteristics of each of the following network topologies (KCSE COMPUTER STUDIES 2021 )

i) Mesh Topology  (2mks)

  • a host/node is connected to one or multiple hosts
  • a   host/node in point to point connection with every other host or a few hosts
  • hosts/nodes in mesh topology also work as relays for other hosts which do not have point-to-point links

(ii) Ring Topology (2mks)

  • each host/node connects exactly to two other hosts
  • data travels around the ring in one direction through all intermediate hosts
  • failure of any host results in the failure of the whole ring

State the characteristics of each of the following network topologies (KCSE COMPUTER STUDIES 2021 )

i) Mesh Topology  (2mks)

  • a host/node is connected to one or multiple hosts
  • a   host/node in point to point connection with every other host or a few hosts
  • hosts/nodes in mesh topology also work as relays for other hosts which do not have point-to-point links

(ii) Ring Topology (2mks)

  • each host/node connects exactly to two other hosts
  • data travels around the ring in one direction through all intermediate hosts
  • failure of any host results in the failure of the whole ring

5 Artificial intelligence is an emerging trend in computer science.
(a) Discuss the use of artificial intelligence by describing some of its characteristics, the ways in which it may be used and the ethical issues associated with its use.
 

Branch of computer science based on enabling computers to
behave like humans/mimic aspects of human intelligence
AI is implemented in software.
Combines psychology, biology, linguistics, mathematics, neuroscience,
and philosophy (ethics)
AI is not the same as the general intelligence of human beings

 

Uses – Any of the following:
Game playing (chess, quiz, video games)
Analytics (analyse buying patterns, predicting behaviours, predictive
text, financial markets)
Image processing (recognising objects/patterns)
Logistics (scheduling, order fulfilment)
Control systems (cars, manufacturing, weapons, navigation)
Expert systems (medical, mechanical, electrical diagnosis)
Neural networks (simulating neuron behaviours as in brains)
Natural languages processing (chatterbots, chatbots, speech
recognition)
Robotics (dangerous situations, help aged or disabled)

 

Ethical issues – Any of the following:
Take the work of humans, thereby affecting employment rates
Is a computer to be trusted to make decisions (life-death)?

If a computer discovers something that humans can’t prove, should it be
accepted as truth?
Do AI machines have rights?
Will people be comfortable interacting with machines that are
considered intelligent?

A company making televisions has introduced robots to replace the human work force.

(a) Describe three effects this would have on the work force

(b) Give two advantages to the company of introducing robots

(c) How could the robots be trained to assemble the televisions?

(d) A whole batch of televisions was produced with some of the parts missing. How could this error have been avoided?

(a) Describe three effects this would have on the work force

  • loss of jobs/unemployment
  • deskilling
  • need to re-train
  • different jobs available/re-skilling
  • no longer need to do hazardous/tedious jobs

(b) Give two advantages to the company of introducing robots

lower work force costs (no salaries to pay)

  • lower environmental costs (less electricity for heating/lighting)
  • higher throughput
  • more consistent product
  • robots don’t need breaks, holidays/work 24/7 etc.
  • robots don’t take industrial action

(c) How could the robots be trained to assemble the televisions?

  • tasks repeated by skilled worker and how each task is done is memorised
  • tasks programmed directly into the computer/robot memor

(d) A whole batch of televisions was produced with some of the parts missing. How could this error have been avoided?

  • if parts missing for a sequence, then a warning should be given and the assembly stopped
  • several quality control stages to spot an error early on
  • program in checks at each stage of assembly so robots can detect a fault immediately

List two types of network software

  • Network operating systems
  • Protocols

KCSE 2002 COMPUTER STUDIES PAPER 1

SECTION A (40 MARKS)

1.Describe the purpose of each of the following computer functional units:    (2mks)

    a) Control

    b) Storage

2.Explain how each of the following would affect the suitability of a room for use as a computer room: (2mks)

a) Burglar proofed door

b)Availability of taps and sinks in the room

3.State three data representation codes used in computers       (3mks)

4.State two types of documentation in program development and give the purpose of each.     (4mks)

5.Suppose a 5 element array A contains the values 9, 12, 17, 7 and 20.  Find the value in A after executing the loop below:

            Repeat for k = 1 to 4

            Set A [k +1]: = A [k]

                        [End of loop]            (3mks)

6.State any three activities that occur in a program compilation process  (3mks)

7.The formula = k20 + P$ 18 was typed in cell L21 and then copied to cell M24 of a spreadsheet. Write the formula as it appears in cell M24.(2mks)

8.State two ways in which a computer may be used in the efficient running of a hospital (2mks)

9.List three disadvantages of using the traditional file management method          (3mks)

10.Give one disadvantage of a single processor multi-user system    (1mk)

11. List three differences between a micro-computer and a super-computer.         (3mks)

12.State and explain two reasons why word processing is one of the most common applications of many computer users.   (2mks)

13. write- 1 in twos complement notation in byte form                                        (4mks)

14.Explain the following input/output terms as used in computer systems. Give an example for each        (4mks)

  a) Read

  b) Write

15.State two disadvantages of networking.

SECTION B (60 MKS)

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

16.The following flowchart can be used to list the odd numbers between 0 and 100

 

 

a)Write a program segment for the flowchart using a high level language.  (7mks)

b)What would be the output from the flowchart if the statement in the decision box is changed to:  (3 mks)

i)          Odd = 100

ii)         Odd< 100

iii)        Odd> 100

c)  Modify the flowchart so that it prints only the sum of the odd number between 0 and 100  (5mks)

17.a)  List five precautions that can be taken to protect data stored in diskettes   (5mks)

b)State and explain two precautions that can be taken to help recover data lost through accidental erasure. (4mks)

   c) Describe each of the following data processing methods:    (6mks)

   i) Batch processing

   ii) Distributed processing

   iii) Multiprogramming

18. a)  i)  What is a computer keyboard?      (1 mk)

           ii)  ist four types of keys found on a computer keyboard.  Give an example of each(4mks)

     b) Give four differences between present day’s computers and the older generation of computers   (4mks)

     c)   i) State three advantages and one disadvantage of using a laser printer.  (4mks)

           ii) Distinguish between a line printer and a page printer             (2mks)

19  a) Identity three public Universities and three National Polytechnics in Kenya where further computer training is offered. In case, state the highest level of qualification that can be acquired in computer training. (6 mks)

b) Distinguish between “Job replacement” and “Job displacement” in reference to computerization.  (2mks)

c) Give four reasons why a firm may decide to computerize its operations.   (4mks)

d) An individual has a right to demand a guarantee of privacy of personal information stored on a computer.Give three such types of information.  (3mks)

20. a)  Give three comparisons of the traditional file management method of typing a document on a typewriter against using a word processor.     (6mks)

      b)  i) Define the term spreadsheet (1 mk)

            ii) Give two examples of spreadsheet packages available in the market today        (2mks)

      c) Explain the following terms as used in a spreadsheet:

             i)  What if …analysis         (2 mks)

             ii) Cell                (1 mk)

             iii) Formula  (1mk)

             iv)  Pie chart                                                                      (2 mks)

Distinguish between transcription and transposition types of errors and give an example of each  (4mks)

Transcription Errors: Transcription errors involve the incorrect entry of data due to mistakes made during the copying or typing process. These errors can occur when transferring information from one source to another.

Transposition Errors: Transposition errors specifically refer to errors where the order of characters or digits is accidentally reversed or swapped. This can happen during manual data entry or when processing information.

Give two examples of each of the following application packages       

a)Spreadsheets                                                                                                                               (2mks)

  • Microsoft Excel
  • Lotus 1-2-3
  • Google Sheets
  • OpenOffice Calc

                                           Any 2 @ 1mk

 

b) Word processors                                                                                                                          (2mks)

  • Microsoft Word
  • Wordpad
  • Corel WordPerfect
  • Lotus Word Pro

 

                                         Any 2 @ 1mk

Mention at least two trends in the technological revolution of computers.

  • Continual decrease in computer size
  • Improved speed and power of processing
  • Decrease in computer physical size and its related facilities cost

Give two benefits for the supermarket manager of using point of sale (POS) terminals.

  • more accurate/improved stock control/recording system/automatic
  • reordering/automatic updating of stock file
  • less staff/wages needed
  • sales statistics now available
  • faster throughput
  • itemised receipt
  • records every transaction
  • records staff work rates
  • less pilfering by staff/easier to identify pilfering
  • less errors
  • faster calculations
  • links to EFTPOS

State two ways in which data validation is implemented on an input form of a database application

  • By setting the validation rule for the input controls on the property sheet in design view
  • By use of VBA to restrict user inputs for a given control on a form
  • By use of queries to restrict options available for the user in a combo box or listbox
  • Setting correct data types for the fields in table the design
  • Enforcing referential integrity in database relationships
  • Use of input mask for the controls on the property sheeet in design view

Briefly describe the information Security principles or CIA triads

  • confidentiality - The principle of protection from unauthorized access or disclosure
  • Integrity - the principle of ensuring that unauthorized or undetected changes to data or system configurations do not occur.
  • Availability - the principle of ensuring that data and services remain accessible to authorized users at all times