• not able to directly manipulate the hardware
• may need to wait for translation before running
• the program may be less efficient.

• A compiled program will only execute on a processor of specific type/family/with same instruction set
• A program run using an interpreter can execute on a computer with any type of processor;

• 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.

– if one station/cable fails, others are not affected
– easier to identify faults when using star topologies
– it is easier to expand this type of network
– performance doesn’t deteriorate under load

- (provides) user interface
– input/output control
– security
– handling interrupts
– spooling
– memory management
– processor management
– utilities (e.g. copy, save, delete, re-name, etc.)
– maintain user accounts
– load/run software
– error reporting/handling
– multiprogramming
– batch processing (JCL)/real time processing
– multitasking/multiuser/multi-access
– file management

Advantages

• It is intuitive
• Easy to navigate
• Uses menus, pointers and icons thus easy to learn and use
• It lets the user exchange data between different software applications
• The user does not have to learn complicated commands

Disadvantages

• Takes a lot of memory
• A lot of processor power is needed
• Takes up a larger amount of hard disk space than other interfaces
• They need significantly more memory (RAM) to run than other interface types

• It is a feature used to prevent unwanted changes to be made on the data contained in a sheet by limiting the ability to make changes

• They run only one program/task
• OS would increase development and manufacturing cost as more storage will be needed

• Websites – any inappropriate websites ie pornography, drugs, guns,
• terrorism etc. e.g. is it acceptable for the organisation to allow access to this
• sort of material when you can’t control who is accessing the service?
• Time – limit amount of time, they may not want to provide indefinite access
• or may want to charge for access after the time limit has expired.
• Preventing file sharing and illegal sharing\use of copyrighted materials.
• Accountability – identification of users and actions on a network by
• preventing anonymous access.
• Prevention of illegal activities such as terrorism and fraud.
• The responsibility to keep children safe and protected.
• Responsibility to keep users (customers) data safe and secure.
• Spoofing of websites, phishing. Responsibility of organisation to put some kind of protection in place, eg filtering of known fraudulent sites.
• Recording of private messages or details if not encrypted.
• Recording of usernames and passwords that the user may also use to access other systems.
• Responsibility of organisation to secure their systems from possible attack.
• Sales and marketing – providing sales leads to market products.

• By use of an ergonomic keyboard
• She should take regular breaks from her computer and stretch her joints
• She should use standard furniture with an upright backrest to reduce strain on the back

• Unsigned integers store more positive values

Legend

• Legends are a small visual representation of the chart's data series to understand each without confusion.

A data series

• is a row or column of numbers that are entered in a worksheet and plotted in your chart, such as a list of quarterly business profits
• A group of related data points or markers that are plotted in charts and graphs

Data Marker

• A symbol on the chart that represents a single value in the worksheet.
• A column, dot, pie slice, or another symbol in the chart that represents a data value

A computer virus is a program designed to damage other programs or causes irregular behaviour in a computer system.

• 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

Virus / trojan / worm / malware

• Piece of software/code/a program that replicates itself  or causes damage e.g. editing/deleting files

Prevention

• Running anti-virus/anti-malware software 
• don’t download from unknown sources
• don’t click on unknown links

Spyware / malware / keylogger

• Piece of software/code/a program that records actions/key presses and sends this data to a third party analysis

Prevention

•  Running anti-spyware/anti-malware software/firewall

Data interception / passive

• Data is sent to another device and is intercepted by a third party

Prevention

• Encryption

Phishing

• An e-mail has a link that when clicked directs the user to a fake website that collects personal data

Prevention

• Network policy // firewall

Pharming

• A piece of code installed that redirects user to fake website that collects personal data

Prevention

• Anti-malware or firewall

Hacker

• Person attempting to gain unauthorised access to the network/computers/ data/files 
• unauthorised access and then deleting/editing data/files

Prevention

• Firewall
• strong password 
• biometrics
• penetration testing

Advantages

– immediate response to questions/queries
– can see each other watch body language etc.
– easier to have several participants (would be difficult using instant messaging if
several people involved)

Disadvantages

– need for expensive equipment/high set up costs
– sometimes synchronisation problems make it difficult for delegates
– need to train people to use the new technology
– greater use of bandwidth

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.

• 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

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)

• has a significantly larger address pool than previous version
• features a client-side address assignment
• has built-in encryption
• enables one device to have many network addresses