admin@kcseforecast.com

Q&A-KCSE Computer Studies Paper 1

Distinguish between a file and a folder

A file is a collection of related data given a unique name while a folder is named storage location on a storage media that contains related files

Question Image

State what is meant by each of the following modes of data  processing

(i) Batch processing.
(ii) Real-time processing.
(iii) Online processing.
(iv) Off-line processing.

(i) Jobs collected together for processing at a later time
(ii) Output produced quickly enough to affect the next input
(iii) User has direct contact with the processor
(iv) User cannot communicate directly with the processor

Question Image

Distinguish between real time processing and interactive processing

  • Real-time processing is where data is processed as it is received and the output is made available immediately to influence the ongoing activity
  • Interactive processing is computer processing in which the user can modify the operations appropriately while observing results at critical steps
Question Image

 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’ 

Question Image

Name three of the stages in the system life cycle

– fact finding
– feasibility study
– analysis
– design
– testing
– documentation
– implementation/changeover/installation
– evaluation
– maintenance

Question Image

Why is 2's complement preferred over 1's complement?

  • two's complement has only one value for zero
Question Image

State four data types used in MS Excel

  • Labels
  • Values
  • Formula
  • Functions
Question Image

Distinguish between Incremental and Full backup


Incremental:

  • Only the changes need to be backed up
  • The software/OS/settings are unlikely to have changed between backups
  • Small number of files likely to be used/edited between backups
  • Take less time to backup
  • Each backup will take less memory space to store

Full:

  • Backup all the data/files and software
  • It might not take a significant time to back up entire system
  • He might only have a small number of files to be backed up each time
  • Safer as have more past versions to revert to
  • User may have changed settings on computer
  • Faster to restore the backup
  • Needs to do a full before he can do an incremental
Question Image

Identify the protocol used to transfer data in networks.

  • TCP/IP
Question Image

KCSE 2003 COMPUTER STUDIES

SECTION A (40 MARKS)

Answer all the questions in this section

1.Computer systems are built from three types of physical components: processors,memories and 1/O devices.

  a) State two tasks of a processor                                                            (2 mks)

  b)State function of 1/O devices                                                               (1 mk)

2. Threats to the safety of computer systems take many forms such as:  white-collar crime, natural disasters, vandalism and carelessness.Give on way as to how each of these forms of threats can be controlled.    2 mks)

3.a) Explain the term nibbles as used in data representation in computers

   b)Perform the following binary arithmetic giving the answers in decimal notation.     (3 mks)

       i)1110.01111 + 11010001 .011

        ii) 1001011.011 - 111.111

     4  a)  Distinguish between machine and assembly language           (2mks)

         b) State the type of translator necessary for a program written in:         (2mks)

            i) High level language

           ii)Assembly language                                                    

5. Briefly explain the purpose of the following types of program documentation: (3mks)

    a)  User manual

     b) Reference guide

     c) Quick reference guide

6. State any two features of a user-friendly program.      (2mks)

7 a) Distinguish between labels and formulae with respect to spreadsheets (2mks)

   b) Consider the entries in the cells below.

 

Cell

B2

B3

C10

C11

C13

Entry

200

100

B2

B3

C10

State the value displayed in cell C13                                      (2 mks)

8.List three differences between wide area Networks (WAN) and Local Area Networks (LAN)      (3mks)

9. Study the flowchart segment below and state the last value printed from the flowchart.         (2 mks)

10.  a) What is an expert system                                                        (1mk)

      b)State any two components of an expert system                     (2mks)

11. give two reasons why optical disks are better storage media compared to floppy diskettes  (2mks)

12.What are the Dos commands used for the following?                       (2mks)

            a) Changing directories

            b) Viewing directories

           c)  Renaming directories

            d) Deleting a directory

13. Distinguish between copying and moving text                                  (2mks)

14. a) Name two methods of paper orientation                                (1mk)

     b)Name two keys used to delete text in a document   (1 mk)

15.Name two features a Database package                                             (2mks)

SECTION B (60 MKS)

Answer question and any other three questions from this section

16.       Study the flowchart below and answer the questions that follow.

 a)Write a high-level language program for the above flowchart (7mks)

 b)List the outputs of the flowchart above                                 (5 mks)

 c) Modify the flowchart so that it adds up all its outputs and displays the sum obtained  (3mks)

17. A computer specification has the following details:

  •  Pentium II
  • 1.44 MB floppy disk drive
  • 20 GB hard disk
  • Full multimedia
  • 17” SVGA monitor
  • Pre-installed operating system
  • Pre-installed office suite

     a)  What is meant by

       i)  1.44 MB floppy disk drive?

       ii)20 GB hard disk?

      iii) 17” SVGA monitor

     b) Which operating system might be pre-installed in this computer and why?         (2mks)

     c) List three multimedia components                                          (3 mks)

      d) i)  what is meant by computer aided manufacture?        (2 mks)

          ii)  Give two examples of computer aided design software.       (2mks)

18. a)Give three examples of network software                                          (3mks)

     b)List any three items that may be referred to as data terminal equipment in a network     (3 mks)

     c)Briefly explain the following terms as used in networking   (4mks)

      i) Remote communication

      ii)Distributed processing

      d) State three advantages and two disadvantages of mesh network topology. (5mks)

19. a)  a company has decided to computerize their operations.  They have decided to purchase package instead of developing their own programs.  Give three advantages and two disadvantages of this approach. 5mks)

      b) i) explain why a value such as 611233444555 may be displayed as ######### When typed in a cell of a spreadsheet (2mks)

       ii)  How can the problem in b (i) above be corrected?      (2mks)

      c) With reasons, briefly describe the most appropriate type of printer output device for the output of:  (6mks)

      i) Customer invoices on multi-part stationery

     ii) Letters to customers

     iii)Detailed engineering designs

20. a)  Distinguish between the following pair of terms                                (6mks)

      i) Data verification and data validation

      ii)Data encryption and passwords

            

Question Image

A computer laboratory experiences power supply problems. Describe three power related problems that should be addressed

Blackout: This is unexpected discontinuation of power supply in the laboratory.

Power sag: Sudden drop of voltage levels that lasts less than a second.

Transients/ surge: High voltage flowing.

Brownout: Partial blackout where there's low voltage flow.

Question Image

State two advantages of electronic databases over a flat file

  • Data Integrity: they provide ways or mechanisms for enforcing data integrity constraints, such as referential integrity. If a record in the parent table is deleted, related records in the child table also get deleted. This ensures accurthe acy and consistency of data stored in the database
  • Data Security
  • Concurrency control
  • Reduces data redundancy
  • Data retrieval and querying
  • Data indexing
  • Data consistency and acid transaction
  • Data backup and recovery
  • Data sharing and collaboration
  • Convenient data maintenance
Question Image

Give one advantage using a star network rather than a ring network.

  • star - if one computer goes down the others can still be used
  • ring - if one computer goes down the others can not be used
Question Image

Explain one drawback to a user if the program is distributed as freeware

The user is not allowed to access the source code so, they cannot tailor the software to their needs and  they cannot fix any bugs in it

The software is still covered by copyright

The user must get the owner’s permission to do anything beyond using it

Question Image

State two advantages and one disadvantage of having a network of computers, rather than a series of stand-alone machines, in a school classroom.

Advantages

  • Sharing of software and data files
  • Sharing of hardware, e.g. printers
  • Communication

Disadvantages

  • Security of files is more of a problem
Question Image

Explain two ways in which an interpreter and a compiler are different.

  • They execute code differently – a compiler reads a complete program at once, an interpreter reads a program line-by-line
  • they identify errors in different ways – a compiler does not allow a program to run until error-free, an interpreter runs the program until the first error.
Question Image

State one ethical responsibility of software users

  • Users need to ensure that their software is licensed
Question Image

Describe the query criteria given below

 

(a) Like "*kenya*"

  • Returns the records of all countries that contain the string "kenya"

(b) Like "*ina"

  • Returns records for all countries/regions whose names end in "ina", such as China and Argentina.

(c) Like U*

  • Returns records for all countries/regions whose names start with "U", such as UK, USA, and so on.

(d) Not Like U*

  • Returns records for all countries/regions whose names start with a character other than "U".

(e) >= "Mexico"

  • Returns records of all countries/regions, beginning with Mexico and continuing through the end of the alphabet.

(f) Like "[A-D]*"

  • Returns records for countries/regions whose names start with the letters "A" through "D".

(g) "USA" Or "UK"

  • Returns records for USA and UK.

https://support.microsoft.com/en-us/office/examples-of-query-criteria-3197228c-8684-4552-ac03-aba746fb29d8

Question Image

Name one item used in the home, other than a computer, that contains a microprocessor.

  • camera
  • microwave
  • washing machine
  • video recorder
  • fridge
  • sewing machine
  • air conditioning
  • games console
  • electronic game electronic toys
  • rice cooker
  • dish washer
  • TV
  • alarm clock
  • radio
Question Image

State advantages of batch processing

  • once instructions are given, the processing runs automatically hence requiring little supervision
  • tasks are processed as a group hence reducing the cost
  • It is faster since the since runs automatically
  • there is increased output since the processor works without any interruption
Question Image