SECTION A (40 MKS)

Answer all the questions in this section.

1. a) What is disk formatting?                                                        (1mk)

b) Indicate whether the following devices are used for input or output  (2mks)

i) Plotter

ii)Light pen

iii)Mouse

iv)Visual display unit

2.a)Explain why the following and give one reason why they are not allowed in a computer laboratory. (2mks)

b) For each of the following give one reason why they are not allowed in a computer laboratory.  (2mks)

i) Smoking

ii)Eating foods

3.Distinguish between Real, integer and Character data types as used in programming (3 mks)

4.The cells k3 to K10 of a worksheet contain remarks on student’s performance such as very good, good, fair and fail depending on the average mark.  Write a formula that can be used to count all students who have the remark “very good”      (3mks)

5.a) State the purpose of registers in a computer system               (1mk)

b)Name two multiprogramming operating systems                   (2 mks)

6.a) A series file comprises of records placed in positions 1 to 10.  State the position of the end of file marker.      (1mk)

  b)State the purpose of each of the following: (2mks)

 i)File server software

ii)Communication software

7.a) Name the control structure depicted by the flowchart below.                   (1 mk)

b)Explain the following terms as used in program implementation.      (2mks)

 i)Parallel running

 ii)Direct change over

8. Consider the linear arrays:

 i) AAA (5:50)

 ii)BBB (-5:10)

 iii)CC (18)

Find the number of elements in each array (3mks)

9.Define the term artificial intelligence  (2 mks)

10.Name two types of relationships that can be applied in database design  (2mks)

11.Explain binary Coded Decimal code of data representation (1 mk)

 a)Indenting

 b)Alignment

 c)Word wrap

12.Outline two ways in which a computer can be used in hotels               (2 Marks)

13.a)Explain Binary Coded Decimal code of data representation (1marks)

 b)Write the number 4110 in BCD notation (1 mk)

14.Arrange the following data units in ascending order of size.

   BYTE, FILE, BIT, NIBBlE     (2mks)

15.State two health issues that may result from prolonged use of computers     (2 mks)

SECTION B (60 MARKS)

16. a) State the stage of program development in which  (4 mk)

i) A flowchart would be drawn

 ii)The programmer would check whether the program does as required

 iii)The user guide would be written

iv)The requirements specifications would be written.

b)State the output of the following flow chart segment                  (1mk)

c) i)Draw a flowchart to compute the combined resistance ® of two resistors R1 and R2 in parallel using the formula;

                      (5mks)

ii)Write a program using Pascal or C languages for the flowchart in C (i) above. (5 ½ mks)

17. a)List three paragraph formatting activities in word processing  (3mks)

 b)Differentiate between bolding and highlighting text (2mks)

c) The following information shows the income and expenditure for “bebayote “ matatu for five days.  The income from Monday to Friday was Kshs. 4,000, 9,000, 10, 000, 15,000 and 12,000 respectively while the expenditure for the same period was Kshs.  2,000, 3,000, 7,000, 5,000 and 6,000 respectively

i)Draw a spreadsheet that would contain the information.  Indicate the rows as 1, 2, 3 …. And the columns as a, B, C    (4mks)

ii)State the expression that would be used to obtain:

 I Monday’s profit  (2mks)

 II Total income (2mks)

III)Highest expenditure (2mks)

18.a) Subtract 0112  from 10012 (1mk)

 b)Using two’s compliment, subtract 7 from 4 and give the answer in decimal notation (4mks)

c) Convert

i) 91B16  to octal    (3mks)

ii) 3768   to hexadecimal   (3mks)

iii) 9.62510 to binary  (4 mks)

19.a) Explain what the following DOS commands will do when executed.

    i)  A: \copy *.* B:    (2 mks)

   ii)   C: \> ERASE*. DOC   (2mks)

  iii)   b: \> Md EXAMS  (2mks)

 b)  i)  With the aid of a diagram, explain hierarchical (tree) network topology   (3mks)

  ii)List two advantages and two disadvantage of hierarchical network topology.  (4 mks)

   Advantages:-

   Disadvantages:

20. a)Name and explain the function of the keyboard keys represented by the following symbols.

  b) Simulation is one of the application areas of computers        

  i) What is meant by the term simulation      (1mk)

  ii)Name two application areas of simulation   (2 mks)

 iii) State three advantages of computer based simulation (3 mks)

 c) Explain three ways in which computers have impacted education (3mks)

(a) Cookies

• Information that a website stores about a user on their hard disk; this enables
  the website to remember details about the user when they next visit the website.

(b) Spyware

• Program installed on a PC to gather information about the user. It monitors
  every key press and relays the information back to the home base

(c) Phishing

• Sending an email that claims to be from a legitimate company; the recipient is then directed to a bogus website where their personal details will be collected

(d)Spam

• Junk/ (unsolicited) electronic mail advertising products and services sent to a general mailing list.

(e) Pharming

• Malicious code installed on a PC or on a server. This code directs users to a
  a fraudulent website without their knowledge.

• consists of values between 0–255 / 0–FFF
• values are separated by full stops/colons
• it is a unique address
• can be static or dynamic
• can be public or private
• can be IPv4 / have four groups of digits
• can be IPv6 / have eight groups of digits
• in IPv6: can replace groups of zeros.

• 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

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)

• A physical file contains the original data whereas a logical file does not contain any data
• A physical file contains one record format while a logical file can contain up to 32 record formats
• A physical file can exist without a logical file while a logical file cannot exist without a physical file

• They are accepted as exhibits in cases of litigation
• Can be used without a computer
• they are difficult to change without leaving any trace

SECTION A (40 MKS)

Answer all the questions in this section in the spaces provided.

1.Describe the computer booting process.    (2 mks)

2. State the functions of the following keys on the computer keyboard   (2 mks)

  a) Backspace

  b)Insert (ins)

3. Jane has noticed the following problems with her computer keyboard    (2mks)

• It is taking a longer time to start-up;
• It is often hanging;
• Applications are taking longer to load.

 State three possible causes of these problems and how they can be solved (3mks)

4 a)Define authenticity as used in software selection  (1mk)

  b) List four ways of acquiring software in an organization     (2mks)

5 some of the storage disk available are:  zip disks, 3 ½ inch floppy disks, DVDs and 5 ¼ inch floppy disks. Arrange these devices in ascending order of storage capacity.    (2mks)

6.You have been asked to change your computer password. State a precaution you need to take in order to avoid each of the following:           

a) Forgetting the password     (1mk)

b) Hacking       (1mk)              

7.State four benefits of using a computer in a school library   (2 mks)

8. Using six bits, find the two’s complement of -2310.     (4 mks)

9. Explain data series, axis and legends as used in spreadsheet charts.  (3mks)

• Data

• Axis

• Legend                       

10. a) Describe the term data integrity.                                            (2 mks)

     b) State four situations in which data may lose integrity.           (2mks)

11.State the function of each of the following:

            a)Network interface card                                                           (1 mk)

            b)Network protocol                                                                    (1 mk)

           c)Hub                                                                                         (1mk)  

12. List four types of publications that can be designed by using desktop publishing software.   (2mks)

13. Differentiate between the following pair of terms as used in database design:

    a)  Input mask and design.                                                           (2 mks)

    b) Table and query                                                                      ( 2mks)

14. List four factors to be considered when purchasing an operating system.     (2mks)

15   Write an algorithm to compute the area of a triangle.   (2mks)

SECTION B (60 MARKS)

Answer question 16 and any other three questions from this section in the spaces provided

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

i) Name the control structures used in the flowchart                 (2mks)

ii) Determine the values of M, N, P and Q.                                ( 4 mks)

M………………………….. N………………………..

P ………………………….. Q ………………………

  iii) Write the pseudo code for the flowchart   (7mks)

 b)  List four functions of an assembler    (2 mks)

17. Define the following web related terms:       

 i)  Web browser   (1mk)

 ii)  Hyperlink      (1mk)

iii) Hypertext document                (1mk)

b)  List six activities performed on the web      (3mks)

c) An institution has ten stand alone computers

i)  Suggest with reasons the most appropriate topology required to inter-connect the computers.   (3mks)

ii) State the necessary steps required to connect the computers to the  internet.      (4mks)

d) Below is an email address:

Name the parts labeled:

                        i)

                        ii)

                        iii)

18.A computer C directory has folders for form 1, form 2, Form 3 and form 4.  Each class has student’s folders labeled according to their number.  The students create their own folder for the subject the are studying based on the table shown below

a)Assuming there is one student per class, draw the corresponding directory tree structure.  (6 mks)

b) i)  a form four student wants to create a folder to store her project. State the path for that project folder.(2 mks)

ii)Suggest how the student can ensure that:

                        1.         Work is not lost in case the hard disk fails.                (1mk)

                        2.         The project is not copied by other students.               (1mk)

c) i).  Other than I/O devices, list other three devices under the control of the operating system.                                                  (3mks)

 ii)Explain any one of the devices named in C (i) above            (1mk)

d)Define the term trouble shooting    (1mk)

19. A manager wishes to replace the current manual system with a computerized one

 a)Describe three main areas that must be evaluated to justify the  replacement   (6mks)

b) List the three areas that would be considered in the requirements specifications.      (3mks)

c)State and explain three ways that can be followed to replace the current system    (6mks)

20. a)  A head teacher keeps the following student details in a database:  Name, Address, Town, Date of Birth, Marks scored, Fees paid.

i)Name the most appropriate primary key. Give a reason      (2mks)

ii)For each item in the student’s details above, indicate its most appropriate data type as used in the database.           (3mks)

iii)Explain why input screens are better data entry designs than entering data directly to a table.        (2mks)

b)List two career opportunities associated with databases.       (2mks)

c)Distinguish between:

i) A table in a word-processing application and a table in a database application (2mks)

ii)Mouse pointer and insertion point.    (2mks)

d)Outline the steps to be followed in order to merge cells in a word processing table.    (2mks)

• Reads the data/packet to find the recipient's address 
• Has physical connections to >=2 different networks
• Holds a routing table
• Stores information about (IP) addresses 
• Keeps packets inside a network by not forwarding them 
• Forwards data / directs/forwards/sends packets 
• Chooses the most efficient path to the next node

 Data

Instructions

•  It does not have declaration part
• It does not  have control structures

RFID stands for radio frequency identification. There is an RFID reader and tag.RFID is used in contactless credit and debit cards as well as in some hotel room cards. Inside an RFID tag is a chip that contains a small amount of memory. The chip is attached to a coil of wire which acts as an antenna. When an RFID tag is scanned, the reader emits radio waves which are picked up by the tag’s antenna. The power induced in the tag’s antenna from these waves is enough to power the chip which then uses its antenna to emit its own radio wave, which contains the information held on the chip. This wave is picked up by the reader which decodes the information and returns the information to a computer.

• To detect and remove errors
• To confirm if the program produces the expected output

• An instruction is retrieved from the memory
• The instruction is decoded
• The instruction is executed
• the program counter is incremented

• Object code refers to a program in machine language while source code to a program in a high level language that must be translated to object code for it to be machine readable

IP spoofing

A technique used to gain unauthorised access to a computer whereby an intruder sends messages to that computer from a false IP address

Back door:
An undocumented method of gaining access to a program, online service or an entire computer system

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

• devices are automatically detected and configured when initially attached
• Impossible to connect device incorrectly/connector only fits one way
• has become the industry standard
• supports multiple data transmission speeds
• lots of support base for USB software developers
• supported by many operating systems
• backward compatible
• faster transmission compared to wireless

• provides an interface between the computer user and the hardware
• Manages the allocation and deallocation of the CPU to processes.
• manages Input-output devices by use of drivers