exam questions

Question 1

Tracking cookies can be created and used when browsing a website.
Describe a security risk associated with tracking cookies.

Answer 1

Unauthorised access to personal
data (sent to third parties
through the tracking cookie)

Question 2

Explain how public and private keys help to keep these details secure when
transmitted between the customer and the bank’s server

Answer 2

 A public key is used to encrypt
the personal data (1)

A private key is used to
decrypt the personal data

Question 3

Describe how watchpoints are used to help programmers locate errors

Answer 3

Watchpoints are used to stop
execution when the value of a
specific variable changes/predetermined conditions are met. (1)

This allows the programmer to
compare the value with the
expected value (1)

Question 4

Describe two benefits of using local variables.

Answer 4

More efficient as memory
assigned to a local variable
becomes available once
function is terminated (1)

Aids modularity (1)

Question 5

Describe the process of usability testing of the new website.

Answer 5

Users given task/scenario to
perform on the software (1)

Feedback is given to
developers (1)

Question 6

Move some cat ears ? State
whether this task is easier to do with the bitmapped or the vector
graphic. Explain your answer

Answer 6

Vector (1 mark)

Ear could be grouped as a set
of objects

Question 7

Describe the effect on the file size of adding the star to both the
vector and bitmapped graphic.

Answer 7

Vector increases

 Bitmap stays the same

Question 8

Describe the steps of

the fetch-execute cycle.

Answer 8

Address of instruction placed
on address bus
 Read line (on control bus) is
activated
 Contents of location
(instruction) transferred to a
register along data bus
 Instruction decoded/executed

Question 9

Explain how cache improves performance

Answer 9

Stores frequently accessed
instructions/data

Faster access times than main
memory

Question 10

Describe the difference between a bit depth of 16 bits and that of 24 bits
for the quality of video.

Answer 10

24 bit can store more than 16 million colours
16 can store 6.5K colours

more colours

Question 11

Pupils access files from a shared folder on their school network server.
These
files are available for the pupils to open, but only a teacher can edit and save
the files to this folder.

Describe how this is implemented.

Answer 11

Pupils have read only access to
this folder (1)
 Teachers have read/write
access to this folder (1)

Question 12

Explain why a compound key is could be required for table

Answer 12

No single field provides a unique

value

Question 13

State two

items that would be specified in a data dictionary.

Answer 13

Field/data type
 Keys / PK/FK
 Validation
 Field length/size
 Format
 Required
 Unique
 Sample data
 Table name

Question 14

State one reason why the increased use of technology has had a negative
effect on the environment.

Answer 14

Answer must refer to
manufacture, use or disposal of
technology.

Question 15

State two benefits of using parameter passing rather than global
variables.

Answer 15

code is more readable/easier to
maintain

Aids modularity

Reduces impact or load on
main memory

Question 16

Explain

what is meant by a function.

Answer 16

Returns a single value

Question 17

Emma’s home computer has a data bus and an address bus.

Describe how each bus is used when reading data from memory.

Answer 17

The address bus
stores/carries/holds the
address of the memory
location of the data (currently
being accessed/read from)
 The data bus transfers data to
the processor/register

Question 18

Other than a trace table, name and describe a technique that Tony could
use to locate and identify the error.

Answer 18

Dry Run or Breakpoint

Manual run through of code often
involving a pen and paper to try to
identify errors

breakpoint- Stop the program

Question 19

Explain the difference between a public key and a private key when securing
the transmission of data.

Answer 19

A public key is used to encrypt the
personal data. (1 mark)
 A private key is used to decrypt the
personal data.

Question 20

Describe an advantage of using Unicode over ASCII, making reference to the
number of bits used to represent a character in each format.

Answer 20

Unicode can represent more
characters.

uses 16 bits compared to 8/7.

Question 21

State other trend that improves performance.
part (a)

Describe how your answer to part (a) improves performance.

Answer 21

 Multi-core/number of processors.
 Increase width of data bus.
 Increase clock speed.
 Increase RAM/memory.
 Increase use of solid state.
 Any other valid response.

Matching reason eg
 Simultaneous execution of
instructions/parallel processing.
 More bits transferred in a single
operation.
 More fetch-executes per clock
pulse.
 Reduces the need/faster access
to access slower backing storage.
 Faster access than slower
backing storage.

Question 22

Using pseudocode or a programming language of your choice,
declare the variable which can store the details of the top 100
movies.

Answer 22

DECLARE topMovies AS ARRAY

OF movie INITIALLY[]*99

Question 23

State the scope of the min variable. Explain your answer.

Answer 23

Local

It is only used within the function
in which it is declared.

Question 24

Explain the role of the memory management function of the operating
system when a user loads the SportsStats program

Answer 24

Tracks/checks available memory.
 Allocates space/addresses in RAM
for the function.
 Protects other processes.

Question 25

John has downloaded a new computer game but finds that it does not run on
his computer

a) State one software reason why the game may not be compatible
(b) State one hardware reason why the game may not be compatible.

Answer 25

part A
Version of/out of date operating system.
 Downloaded file is corrupt

Part B 
Insufficient amount of RAM/memory.
 Minimum clock speed not available.
 Version of processor.
 Version of graphics card

Question 26

SecureBell stores customer videos on a public cloud.
(i) State two reasons why SecureBell chooses to use a public cloud
rather than a private cloud to store the videos.

Answer 26

Public cloud services can be easily increased or decreased to match current needs.

 Can set up or easily expand capacity of public cloud storage without (Securebell) purchasing hardware.

 Public cloud removes need for backup/maintenance/ administration strategies (for SecureBell).

 Public cloud has lower initial costs than private cloud.

Question 27

Say the Update

Delete

Insert

Querys

Answer 27

Update
Set
Where

Insert Into
values

Delete From
Where

Question 28

Explain why tracking cookies are also known as third-party cookies.

Answer 28

Tracking cookies do not originate from the website

operator/owner but from a third party – such as an

advertiser or social network. (1 mark) 1

Question 29

Describe the following type of DOS attack:

Domain Name Service

Answer 29

A large volume of DNS queries to different DNS servers are made at the same time using a spoofed address of the target service. The DNS servers return responses overloading the attacked system and a denial of service to legitimate users.

Question 30

A real number is stored using 32-bit floating point representation. The
mantissa is allocated 24 bits and 8 bits are allocated to the exponent.
Describe the effect if the allocation is changed to a 16-bit mantissa and a
16-bit exponent.

Answer 30

Precision will decrease (1)

 Range will increase

Question 31

Explain how multi-core processors are used as a technique to

increase processor performance

Answer 31

Each core is a separate processing unit
within the processor (1 mark). Adding
additional cores allows the processor to
run execute multiple instructions at the
same time (1 mark)