paper 2 exam q

Question 1

A minimum color depth of two bits is needed to store the image. Explain how the image in can be represented as a bitmap. (3 marks)

Answer 1

The pixels are stored consecutively (1)

each color could be represented by a unique 2-bit pattern (1)

. the bitmap will need the width and height included (1)

Question 2

Give one reason why a CPU with two cores might perform faster than an equivalent CPU with only one core. (1)

Answer 2

The processor with two cores may be able to process two instructions simultaneously (1)

Question 3

Give one example of a type of volatile memory in a computer system (1 mark)

Answer 3

RAM

Question 4

Explain why secondary storage is required in a computer system. (2 marks)

Answer 4

For Storing data / files (1) using non-volatile storage (1)

Question 5

Explain the role of main memory in the execute stage of the Fetch-Execute cycle.(2 marks)

Answer 5

Data required by an instruction may be fetched from main memory (1)

Result of instruction may be stored in main memory (2)

Question 6

State one advantage of writing programs in assembly language instead of a high-level language. (1 marks)

Answer 6

Programs written in assembly language run faster (1)

Question 7

Describe two differences between a PAN and a WAN (2 marks)

Answer 7

PAN centered round a person (1) PAN and WAN use different protocols (2)

Question 8

State two differences between a bus topology and a star topology (2 marks)

Answer 8

A bus network has all computers connected to a backbone (1)

All devices / computers on a bus network see all data transmitted (1)

Question 9

What are 2 benefits of relational databases? (2)

Answer 9

Redundant data is less likely to be stored (1)

There are less likely to be data inconsistences (1)

Question 10

State 4 functions of an operation system (4)

Answer 10

Process management (1)
Memory management (1)
Applications management (1)
Security management (1)

Question 11

State 2 statements about code written in low-level language than high-level language. (2 marks)

Answer 11

Code is not translated using a compiler (1)
Code can directly manipulate computer registers (2)

Question 12

State the purpose of an assembler (1)

Answer 12

To translate assembly language into machine code (1)

Question 13

Explain how an interpreter works (4 marks)

Answer 13

-they don’t produce machine code so program needs to be translated every execution (1)
-call machine code subroutines in their own code to carry out commands (1)
-they translate line at a time which is then executed (1)
-if a runtime error is found then interpreter stops (1)

Question 14

State 2 reasons why computers have more RAM then cache memory (2)

Answer 14

RAM is cheaper per byte (1)

Capacity of cache cannot store both data and programs (1)

Question 15

State 2 advantages of using cloud storage over local storage (2)

Answer 15

Enables user to access data from more places (1)

Enables user to share data more easily with users (1)

Question 16

Explain why solid-state storage is not fitted into every computer (2)

Answer 16

SSDs are expensive / higher cost per gigabyte (1)

SSDs have lower capacity (1)

Question 17

State 1 disadvantage of higher sample sound resolution (1)

Answer 17

Higher file size / sound files will take longer to download / uses more memory processing when recording (1)

Question 18

State 2 issues with only using username and password when authenticating a user (2 marks)

Answer 18

Weak passwords are easily guessed(1)

Username/passwords may have appeared in a data leak (1)

Question 19

describe one security measure that could be used in addition to a password that could be used to check authenticity (2)

Answer 19

-biometrics; compare data to user’s unique biometric data (1)

-authenticator app on phone; generates a code that user can input to log-in (1)

Question 20

State 2 reasons why automatic software updates provide better security than manual software updates (2)

Answer 20

-user may forget to do updates manually (1)

-automatic updates mean that computer is protected more quickly (1)

Question 21

Sate 2 reasons why data is compressed (2)

Answer 21

-to reduce file size (1)

-to make it faster to transmit (1)

Question 22

Define the term relational data base (2)

Answer 22

Database with multiple tables (1) that are linked together (1)

Question 23

state 1 benefit of using relational databases (1)

Answer 23

Reduces data inconsistency

Question 24

explain what effects increasing the sample rate would have on the recording (2)

Answer 24

File size would increase (1)
The more samples per second, the more accurate the sound is (1)

Question 25

State 2 functions of an operating system (2)

Answer 25

Application management
Process management

Question 26

State 2 correct facts about RAM (2)

Answer 26

Used for main memory (1)
it is volatile memory (1)

Question 27

Explain how clock speed affects CPU performance (2)

Answer 27

The more pulses per second, the more fetch-execute cycles (1)

Each instruction starts on a clock pulse (1)

Question 28

Explain how the number of processer cores affects CPU performance (2)

Answer 28

Affects the number of instructions that can be executed simultaneously (1)

Each processor core can fetch and execute its own instructions (1)

Question 29

Explain how cache size affects the CPU performance (2)

Answer 29

Instructions take less time to transfer to the processor from cache (1)

Because cache is held closer to the processor (1)

Question 30

Define the term computer network (2)

Answer 30

2 or more computers (1) Connected together (1)

Question 31

Explain how a firewall can be used to improve the security of a network (2)

Answer 31

Acts as a barrier between a computer and external devices (1)

Inspects incoming and outgoing packets of data (1)

Question 32

Describe 2 differences between an embedded-system and a non-embedded system (2)

Answer 32

Embedded systems have specific purpose, non-embedded have a general purpose (1)

Embedded-systems have small amount of memory compared to non-embedded (1)

Question 33

Give 3 examples of when it would be suitable to use a CAPTCHA system (3)

Answer 33

Account registration (1)

Account access (1)

Online voting system (1)