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Form 3 COMPUTER STUDIES Specimen ofAnnual Exam
1 What are each of these called?
a) The input device that enables people with
special needs to control a mouse pointer on the
screen
b) The non removable storage medium which stores
non-volatile memory
c) Copies of data files done to restore the system
in case data is lost.
d) An input device which is used to validate bank
cheques
e) A magnetic storage device that is the main
form of backing (secondary) store in computer
systems.
f) An old storage device which used to store just
1.44Mb of data
g) An input device which reads pencil marks in
specific areas of a page
Name & Surname:
Directions:
Answer all questions
All answers are to be written on this booklet
The use of calculators is NOT allowed
Good English and orderly presentation is important, however no marks will be deducted for
spelling or grammar mistakes.
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h) A very small 2-state hardware item that can
either output a 1 or a 0.
i) A standard character code that is widely used in
computers
j) A network which is located at far away
distances across towns and countries
k) A gate that has only one input and one output
l) A method of validating data where acceptable
values have to be from a predetermined set.
2. Fill in the table below to obtain the conversion of each number in binary (8 bit),
hexadecimal and decimal.
Binary Hexadecimal Decimal
1 0 0 1 1 1 0 1
C6
175
Working:
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3. Circle the invalid numbers in the following list:
10010 1210 10012 60016
20516 2H16 1BC2 A12
4. Name a type of application software that you would use to do the following:
View a video on YouTube
Type a letter and perform mail merge
Send an email to a colleague
Deliver a presentation to an audience
Build a school magazine
Check your computer for any malicious programme
Answer the following questions on storage:
a) Why is software nowadays being provided on DVD’s rather than CDs?
_____________________________________________________________________________________
_____________________________________________________________________________________
b) Why do you think software has to be installed on the hard disk and not run directly from an optical
disk?
_____________________________________________________________________________________
_____________________________________________________________________________________
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c) Explain the difference and give one example of the following storage types?
Explanation Example
Optical Storage
Magnetic Storage
Flash Memory
d) What measures should be taken to prevent data from being lost?
_____________________________________________________________________________________
_____________________________________________________________________________________
e) Explain what is meant by the Transaction File - Master File Update System.
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
5. The CPU consists of 3 main parts. Mention which are these 3 parts, and explain their use.
Abbreviation Name in Full Use
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6. A typical computer system has both Main Memory and Backing (Secondary) Storage.
a) Main Memory is made up of two memories, these are the _______________ and the
______________.
b) Why is Main Memory an essential part of the computer system?
_____________________________________________________________________________________
_____________________________________________________________________________________
c) What do the acronyms RAM and ROM stand for?
RAM: _________________________________ ROM: __________________________________
d) Write down two differences between the RAM and the ROM:
RAM ROM
7. Consider the following Logic Circuit:
a) Complete the truth table below for this logic circuit b) The missing logic Gate is _______
A B X Y Z
0 0
0 1 0
1
0
c) Which logic gate does the same function as the entire logic circuit ? ________
d) Give the Boolean expression of the above logic circuit.
___________________________________
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8. Draw Arrows to match the following storage media with their typical capacities.
Storage Media Capacity
CD ROM 4.7GB
Hard Disk 650MB
Pen Drive 500GB
DVD-ROM 16GB
What is the difference between direct access and serial access? Support your answer with examples.
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Give one application where direct access would be ideal
_____________________________________________________________________________________
Give one application where serial access would be ideal
____________________________________________________________________________________
Mention one storage medium which is only capable of serial access
_________________________________________
Suggest one disadvantage of serial access
_____________________________________________________________________________________
_____________________________________________________________________________________
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9. Data Representation
a) What is the maximum number that may be represented in an 8-bit register?
_________________________________________________________________
b) A character set consists of 225 different characters. What is the minimum
number of bits required to represent all this character set? Explain Why.
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
c) Given that an ASCII-type coding system codes the letter A with the decimal
number 6510, what binary number is used to code the (capital) letter M? [1]
____________________________________________________________________
d) Why is it desirable to have standard character coding systems? [2]
____________________________________________________________________
____________________________________________________________________
10. The GUI New Question :
a) What is the GUI ?
_______________________________________________________________________________
_______________________________________________________________________________
b) List TWO features of the GUI
- ____________________________________________________________
- ____________________________________________________________
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Page 8 of 12
11. The internet: The Internet has various applications in the business world.
a. Mention one advantage of using e-mail for business communication.
_____________________________________________________________________________________
_____________________________________________________________________________________
b. Suggest two other uses (except email) of the Internet in the business world.
i. _____________________
ii. ____________________
c. “ The WWW is different from the Internet”. Is this statement True or False? Explain your answer.
_____________________________________________________________________________________
_____________________________________________________________________________________
d. Explain the difference between a Search engine and a web browser.
_____________________________________________________________________________________
_____________________________________________________________________________________
Give an example of a search engine and of a web browser. [1]
Search Engine _____________________________; Web Browser____________________________
e. What do the following abbreviations stand for?
i) WWW _______________________________________________
ii) HTML _______________________________________________
iii) URL ________________________________________________
iv) HTTP________________________________________________
v) ISP _________________________________________________
vi) FTP _________________________________________________
f. Why is an ISP required for an Internet connection? [1]
___________________________________________________________________
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Page 9 of 12
12. Databases: A DVD rental shop keeps a computerised database of all the DVDs. It has a DVD table
in which each record about a DVD is has the following fields:
Give a suitable data type for each of the fields :
DVD Number
DVD Name
Genre
Date of Release
Available
Main Actors
a) Which of the mentioned fields can be used as a key field? _________________
b) The shop needs another table called the RENTALS table, which will keep record the list of
customers which have rented a DVD. Mention at least THREE fields which are required in this
table.
c) The DVD table and RENTALS table are linked together.
i. Identify which field/s are used to link these two tables.
________________________________________________________________________
________________________________________________________________________
ii. Explain the type of relationship created between these two tables.
________________________________________________________________________
________________________________________________________________________
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Define the following terms as used in databases :
iii. Record
________________________________________________________________________
________________________________________________________________________
______________________________________________________________________
iv. Query
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
v. Keyfield
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
13. What is the difference between analogue and digital data? Draw their respective graph, and
mention an analogue and a digital device.
Analogue:____________________________________________________________________________
Digital: ______________________________________________________________________________
Analogue
Graph
Analogue Device:
_______________________
Digital Graph
Digital Device:
________________________
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14.For each of the following statements tick () True or False in the respective column
True False
OCR stands for Optical Character Recognition
The decimal number system is made up of ten digits
Formatting a disk will not delete any data that is present in the disk
Google is an example of a web browser
The ISP is an example of a search engine
A scanner, a monitor and a touchpad are all input devices
Main memory is used to store installed programs
You can send and receive an email even if you are offline
Serial access does not have to be sequential
The Hard Disk is part of a computer’s secondary storage
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15. Consider the Truth Table Below.
a) Draw the logic circuit representing this truth table
b) Give the Boolean expression of the circuit
__________________________________________________________________________
16. Draw the logic circuit of the following Boolean Expression:
D = (A AND B) OR (NOT(B AND C))
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