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Computer Studies 2210 March, 2015 Worksheet
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Question 1 What is bespoke soft ware and what are its advantages
and disadvantages compared to generic application soft ware?
Question 2 Connect the task on the left to the most appropriate
type of soft ware on the right.
Question 3 Robots are used to do many jobs.
a. Describe a job and say why robots are used to do it. (Job
& Reason) b. Describe two jobs which robots cannot do. (Jobs
& Reasons)
Question 4 Computer-aided design (CAD) is one of the most widely
used commercial applications of computer graphics.
a. Name two areas in which CAD could be used. b. Give three
features you might expect a CAD program to contain.
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Computer Studies 2210 March, 2015 Worksheet
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Question 5 An estate agent uses a computer system to store
details about properties for sale. A section of the properties file
is shown below:
a. Why is coded data used for Type? b. What is the data type for
Price? c. What is meant by a key field? Which is the key field?
Question 6 A second-hand bookstore has 2000 books and magazines
in stock. Each item has a unique five-digit code with the first
digit identifying the type of item:
1 = hardback non-fiction 2 = hardback fiction 3 = paperback 4 =
magazine 5 = comic book
For example, in the code 10379 the 1 identifies that it is a
hardback non-fiction book; in the code 41055 the 4 identifies the
item as a magazine. Write an algorithm, using pseudocode or
otherwise, that:
inputs the codes for all 2000 items
validates the input code
calculates how many of each category are in stock
outputs the five totals.
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Computer Studies 2210 March, 2015 Worksheet
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Question 7 Explain the following terms:
a. Database b. file c. direct access file d. record e.
sequential file
Question 8
a. What is meant by the term validation? b. What is meant by the
term verification? c. Describe one method of verification when
changing a password.
Question 9 In a chemical plant, the temperature is taken at the
start and end of each batch and the volume of gas are measured. The
following spreadsheet shows a set of measurements.
A B C D D F
1
Batch
Start temperature
End temperature
Temp rise
Gas volume
Volume/ temp rise
2 11 16 28 12 60 5.0
3 12 20 35 15 80 5.3
4 13 15 30 15 75 5.0
5 14 19 33 14 90 6.4
6 15 18 36 18 100 5.6
7 16 17 35 18 110 6.1
8 17 20 38 18 105 5.8
9 18 21 37 16 100 6.3
10 Mean temperature rise = 15.75 Maximum ration 6.4
a. What is the formula to find the temperature rise for Batch
15? b. What is the formula to find the mean (average) temperature
rise for all the batches? c. What is the formula for the maximum
ratio? d. How can you repeat the formula in F2 in cells F3 to F9
without typing it out another seven
times? Question 10 Define the term backing storage and explain
why computers need backing storage. Question 11 ROM and RAM are two
types of memory found in computers.
a. What do the letters ROM stand for? b. What do the letters RAM
stand for? c. What is the main difference between RAM and ROM?
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Computer Studies 2210 March, 2015 Worksheet
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d. Complete the following statements with RAM, ROM, backing
storage. i. .......... stores a copy of your work when the computer
is switched off .
ii. .......... stores application programs and data while the
computer is running. iii. .......... stores programs that must be
available as soon as the computer is switched on.
Question 12 The following algorithm accepts 30 test scores and
outputs the smallest, the largest and the average.
10 Largest 0
20 Smallest 0
30 Total 0
40 FOR x 0 TO 30
50 INPUT Score
60 Total Total + Score
70 IF Score > Largest THEN Largest Score
80 IF Score < Smallest THEN Smallest Score
90 x x + 1
100 NEXT
110 OUTPUT Largest, Smallest, Total / x
There are three errors in this algorithm. Locate these errors
and suggest what changes should be made to the algorithm. (Errors
and Corrections) Question 13 Describe the features of:
a. a command line interface; b. a graphical user interface.
Question 14 Draw a diagram to explain how folders are structured
on a hard disk. Question 15 Explain the meaning of these computer
terms:
a. buffer b. peripheral device c. interrupt d. polling e.
handshaking
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Computer Studies 2210 March, 2015 Worksheet
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Question 16 Copy and complete the truth table for the following
logic circuit:
A B C X
Question 17 Describe a batch processing system, using the
example of a specific application. Question 18 Consider the
following flowchart: Create a trace table for the flowchart if the
values of s input are: 30, 6, 60, 45, 60, 15, 30, 30, 15, 12 x s
Result Output
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Computer Studies 2210 March, 2015 Worksheet
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Question 19 Describe three network topologies, including a
sketch Question 20
a. What is an intranet and why is it used? b. What is the
difference between an intranet and the Internet?
Question 21 Onboard computers allow aeroplanes to operate more
efficiently and safely.
a. How is data collected during a flight? b. Describe how the
computer would know when to make course corrections during a
flight. c. Give two advantages of a computer system over a human
pilot. d. Why do all flights still have human pilots?
Question 22 Name the stages of the system life cycle. Question
23 A regional boiler repair company with four branches wants to
change from a manual stock control system to a computerised stock
control system.
a. State three reasons why the manager would want a computerised
system. b. Describe three methods of fact finding that would be
used to analyse the manual stock control
system. Question 24 A small business has decided to change from
a manual wages system to a computerised wages system for producing
the employees pay.
a. State three tasks in the analysis of the existing system. b.
State three types of test data that should be used to test the
program. c. Name the three different types of system maintenance
that might be required by the new
system. Question 25 Describe four methods of system
implementation. For each method of implementation, identify a
situation where it is most suitable. Question 26 Users of the
Internet can save money compared to people who are not online. Give
two examples of online services that allow users to save money and
describe how the Internet has made these savings possible.
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Computer Studies 2210 March, 2015 Worksheet
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Question 27 The e temperature and soil moisture of a greenhouse
must be controlled and must remain within a certain range. The e
temperature must be kept between 5C and 30C and the soil must not
get too dry. Describe in detail how a computer system could be used
to monitor and control both temperature and soil moisture in the
greenhouse. In your answer state what items of hardware or
equipment might be needed Question 28 Robots are now used in many
different situations.
a. Name two different sensors that can be fitted to robots. b.
Describe how each of these sensors could be used. c. List three
jobs done by robots. d. Give three reasons for using robots instead
of people.
Question 29 A multimedia presentation needs to use photographs
taken by a digital camera. The photographs are transferred to a
computer.
a. State two types of change that can be made to the photographs
using graphics software. b. Describe how edited photographs can be
inserted into the presentation. c. State one multimedia element,
other than graphics and text that could be included in the
presentation. Question 30 A spreadsheet could be used to produce
a simulation model.
a. Give a definition of a simulation model and state one example
of where a simulation model could be used.
b. Give an advantage of using a simulation model. Question 31 A
number of schools are considering using video conferencing.
a. What is meant by video conferencing? b. The schools already
have computers. Give two additional pieces of hardware needed to
enable
video conferencing. c. Give two advantages to the schools of
using video conferencing.
Question 32 A manufacturer of digital cameras employs 12 people
to answer technical queries over the telephone. The company has
decided to develop a website to answer customer queries.
a. Describe two ways this change would affect the 12 employees.
b. Describe two advantages to the company of introducing this
system. c. Describe two advantages to the customer of using this
system.
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Computer Studies 2210 March, 2015 Worksheet
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Question 33 a. What is meant by soft ware copyright? b. Define
the term computer virus. c. What is meant by the term
de-skilling?
Question 34
a. What is meant by teleworking? b. What hardware and soft ware
is needed by a teleworker? c. Give two advantages of teleworking
for the employer. d. Give two advantages of teleworking for the
employee.
Question 35 A doctors clinic decides to network its computers
and allow Internet access on them. Patient records are stored on a
computer linked to the network, to allow doctors to access
information from any computer in the clinic.
a. Describe two problems this could create and how the system
could be protected against these problems. (Problems and
Protections)
b. How is it possible to prevent unauthorised access to patient
records? c. Each patient record is approximately five megabytes.
Suggest a possible backup device to
store the records. Question 36 List three principles on which
data protection legislation is based. Question 37 Bytes of data
transferred using a serial cable are checked for errors at the
receiving end using an even/odd parity checks.
a) Suppose you are using an even parity. What should the binary
word 1010 look like after
you add a parity bit? b) Suppose you are using an odd parity.
What should the binary word 1010 look like after
you add the parity bit? c) How can any errors be corrected?
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Computer Studies 2210 March, 2015 Worksheet
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Question 38 Consider the following algorithm.
a. Write down the output if the two numbers input are 4 and 3.
(a = 4 and b = 3.)
b. Explain why an algorithm is written as a subroutine
(procedure) and stored in a program library.
Question 39 Computer models are used to forecast the paths of
hurricanes.
a. Describe how data is gathered for the computer model. b. How
does the computer model make its forecast based on the input data?
c. Describe two ways the forecast could be conveyed to the
user.
Question 40 A student gave the following three computer
definitions.
Give the name of the term being described in each case.
a. a signal from a device sent to a computer causing the CPU to
stop its current operation
temporarily b. unique ID for a network interface card c. an
exchange of signals between two devices when communicating to
ensure
synchronisation d. numerical ID for each device on the Internet
e. a temporary memory to store data waiting to be sent to a
device
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Computer Studies 2210 March, 2015 Worksheet
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Question 41 Read this algorithm. Set Result to 0 INPUT Number
WHILE Number >= 0
DO IF Number > Result THEN Result Number INPUT Number
ENDWHILE OUTPUT Result
a. What is the purpose of this algorithm? b. What value of input
will stop the loop and output the answer? c. Copy and complete the
following trace table for the input values 6, 12, 8 and 3.
Question 42 Draw the logic circuit required to fulfill the
following statements:
a. Output C = (NOT(A AND B)) AND (A OR B) b. Light (L) is on if
Switch A is on OR (Switch B is on AND Input C is off ).
Question 43 Name two household devices that are controlled by a
microprocessor and do not need an operating system. For each,
explain why an operating system is not necessary.
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Computer Studies 2210 March, 2015 Worksheet
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Question 44 Consider the following
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Computer Studies 2210 March, 2015 Worksheet
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Complete the following trace table using the temperature values
14, 17, 23, 27, 29, 30, 32, 26, 18, 12.
Question 45 A piece of pseudocode was written to input 1000
positive numbers and then output the highest and lowest
numbers.
10 highest = 0 20 lowest = 0 30 for count = 1 to 100 40 input
number 50 if number > highest then number = highest 60 if number
< lowest then number = lowest 70 count = count + 1 80 next
counts 90 print highest, lowest
There are errors in the code. Locate these errors and suggest a
correction. Question 46 A country has four mobile phone network
operators. Each mobile phone number has eight digits. The first
three digits identify the network operator:
444 Yodafone 555 N2 network 666 Kofee mobile 777 Satsuma
mobile
Write an algorithm, using pseudocode or flowchart only, which
reads 50 000 eight-digit mobile phone calls made during the day and
outputs the number of calls made on each of the four networks.
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Computer Studies 2210 March, 2015 Worksheet
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Question 47 Some decorative lights are made up from a cluster of
red, blue, green, yellow and white LEDs. Each colour is represented
by a binary code:
A 6-bit register, R1, stores the 1-values to represent a
sequence of colours. Thus, if R1 contains:
this means the blue, yellow and black colour sequence is stored
and displayed in that order. The length of time each light is on is
set by a binary value in another register, R2: Thus
means each colour is on for 2 seconds.
a. The two registers contain the following values. What is the
sequence of coloured lights and the timing for each colour?
b. What will the two registers contain if the coloured light
sequence is red, green and black and the timing is 5 seconds?
c. What is the problem with trying to display green, blue, red
in that order?
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Computer Studies 2210 March, 2015 Worksheet
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Question 48 a. Show whether the following identification numbers
are valid or not. You must show how you
arrived at your answer with the help of 11s method. I. 4 2 1 9 2
3
II. 8 2 0 1 5 6 b. Find the check digit for the following
identification number:
5 0 2 4 1 __
Question 49 A floor turtle can use the following
instructions:
(Each square in the drawing below is 10 cm by 10 cm.)
Complete the set of instructions to draw the above shape (shown
in bold lines) using REPEAT at least once.
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Computer Studies 2210 March, 2015 Worksheet
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Question 50 A town contains 5000 houses. Each house owner must
pay tax based on the value of the house. Houses over $200 000 pay
2% of their value in tax, houses over $100 000 pay 1.5% of their
value in tax and houses over $50 000 pay 1% of their value in tax.
All others pay no tax. Write an algorithm to solve this problem.
(Solve this algorithm with the help of WHILEDO loop). Question 51
a. The systems analyst needs to ensure that the project is
delivered on time and on .budget. Explain
why the systems analyst has chosen to use a Gantt chart rather
than a PERT chart to track the progress of this project.
b. The systems analyst has decided to use the following methods
to gather information about the existing manual system.
A questionnaire for the parents
An interview for the school office staff Explain why each of the
methods used was appropriate for this manual system.
Question 52 The rail network consists of 10 stations. The fare
between each station is $2. There is a 10% discount when 3 or more
passengers travel together. Tickets can be purchased at any station
using automated terminals. Write an algorithm for the automated
terminals to:
input the starting station number, the destination station
number and the number of passengers
calculate the total fare and output the amount to be paid
calculate the change (if any)
issue the rail ticket(s) and change (Solve this algorithm with
the help of REPEATUNTIL and FORNEXT loop). Question 53 A user
wishes to use a word processing application. They can either use a
command line interface (CLI) or a graphical user interface (GUI) to
open this application.
a) Describe how both methods could be used to select the
application including any input hardware needed.
b) What is meant by automatic data capture? c) Name a device
used in automatic data capture and describe an application that
uses it