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Edexcel GCSE Computer Science (1CP2) Exam Questions

Build a practice paper from 693 exam-style questions, each with its mark scheme and example answers. Print it, or answer it on paper and then open the mark schemes. Or browse the questions by topic.

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3 questions · 5 marks

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1Multiple choice1 markCompression Swap Remove

Identify the statement that describes lossless compression.

[1 mark]
  • AData is encrypted so that it cannot be read by others
  • BData is permanently removed to make the file smaller
  • CNo data is lost and the original file can be recreated
  • DThe file is split into packets that are sent separately
Mark scheme
  • C No data is lost and the original file can be recreated (1)
  • The only correct answer is C. The correct answer is no data is lost and the original file can be recreated.
  • A is not correct because encryption hides data and does not make the file smaller
  • B is not correct because permanently removing data is lossy compression
  • D is not correct because splitting a file into packets is part of transmission, not compression
Example answers and how they were marked
Full marks1/1

C No data is lost and the original file can be recreated

Why: Correct option (1).

No marks0/1

B Data is permanently removed to make the file smaller

Why: Near miss: this is lossy compression, not lossless, so no mark.

No marks0/1

D The file is split into packets that are sent separately

Why: Misconception that compression is packet switching; no mark.

2Short recall2 marksWired Connections Swap Remove

A school connects its desktop computers to the network using cables.

Give two reasons why the wired connections give better network performance than the wireless connections.

[2 marks]
Mark scheme

Award one mark for any of the following up to a maximum of two marks:

  • Faster transmission speed (1)
  • Higher bandwidth (1)
  • Lower latency (1)
  • Not affected by interference (from other devices/walls) (1)
  • No blind spots/not affected by distance from the wireless access point (1)

Do not accept benefits of wireless connections, e.g. users can move around the building with their devices

Do not accept 'easier to set up' or 'does not need a password' as these are not about network performance

Example answers and how they were marked
Full marks2/2

The wired connection is not affected by interference from other devices, and it has a lower latency than Wi-Fi.

Why: Interference point (1) and lower latency point (1).

Some marks1/2

It has a faster transmission speed and the users can move around the building with their computers.

Why: Faster transmission speed (1); moving around is a benefit of wireless, so is not credited.

No marks0/2

It is easier to set up the network and the users do not need a password.

Why: Neither point is about network performance; the mark scheme does not accept 'easier to set up' or password points, so no marks.

3Short recall2 marksCompression Swap Remove

Files can be compressed before they are stored.

Define the term lossless compression.

[2 marks]
Mark scheme

Award one mark for any of the following up to a maximum of two marks:

  • Reduces/makes the size of a file smaller (1)
  • No data is lost/removed (during compression) (1)
  • The original file/data can be recreated/restored exactly (1)

Allow 'the compressed file takes up less storage space' for the first mark.

The second and third bullets are two ways of making the same point: award a maximum of one mark for them, so a response that says no data is lost and that the original file can be restored, but does not say the file is smaller, scores one mark.

Do not accept descriptions of lossy compression, e.g. 'it removes data that is not needed to make the file smaller'.

Ignore reference to download/transmission times, bandwidth and streaming, as these are benefits of compression and not part of the definition.

Example answers and how they were marked
Full marks2/2

Lossless compression reduces the size of a file without permanently removing any data, so the original file can be restored exactly.

Why: Reduces the size of a file (1) and no data is lost, so the original can be restored exactly (1); maximum of two marks reached.

Some marks1/2

It makes a file smaller so it downloads more quickly.

Why: Reduces the size of a file (1); the faster download is ignored as a benefit, not part of the definition.

No marks0/2

It removes data that is not needed to make the file smaller.

Why: Describes lossy compression, which the do-not-accept line rules out, so the mention of making the file smaller is not credited.

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