AQA GCSE Computer Science Paper 2: Computing concepts June 2024 question paper 8525/2

Which statement best describes what computers represent using binary?

Shade one lozenge.

Convert the binary number 10110111 into decimal.

Convert the decimal number 112 into hexadecimal.

You should show your working.

Figure 1 shows a bit pattern.

Figure 1

00110011

State the result of applying a left binary shift of two to the bit pattern shown in Figure 1.

The decimal equivalent of the bit pattern shown in Figure 1 is 51

State the result of applying a left binary shift of one to the bit pattern shown in Figure 1.

Give your answer in decimal.

Which statement best describes where a single binary shift can be used?

Shade one lozenge.

Figure 2 shows four bitmap images.

State the number of pixels in Image A in Figure 2.

State the minimum colour depth required to represent Image B in Figure 2.

Calculate the minimum amount of storage required to store Image D from Figure 2.

Give your answer in bytes.

Show your working.

Figure 2 has been included again below.

Figure 3 shows how Image D can be represented as binary data.

Complete the table to show the binary representation of each colour in Image D.

The number of colours used in Image C and Image D in Figure 2 are both increased by one.

State the impact of this increase on the minimum file sizes of both Image C and Image D.

Image C

Image D

Calculate the number of bits in 7 MB.

Show your working.

bits

Figure 4 shows a logic gate.

Figure 5 shows a truth table.

Complete the logic circuit by writing the name of a logic gate in each empty box.

The completed logic circuit should have the same functionality as the circuit represented by the truth table in Figure 5.

You should write the name of one logic gate only in each box.

Figure 6 shows a different logic circuit.

Write a Boolean expression that represents the logic circuit shown in Figure 6.

You must use the correct symbols for the Boolean operators in your expression.

Three major components of a Central Processing Unit (CPU) are:

• control unit

• clock

• cache.

Describe the function of each of the three components.

Control unit

Clock

Cache

Explain three ways to improve the performance of a CPU.

Figure 7 contains a Huffman tree.

The Huffman tree in Figure 7 was used to encode a string, which resulted in the following bit pattern: 0001011001 State the string that this bit pattern represents.

Which two statements are true about machine code?

Shade two lozenges.

Describe three differences between high-level programming languages and low-level programming languages.

Describe how compilers and interpreters operate.

Define the term computer network.

A school has purchased new computers for students and staff to use.

The school is considering installing the computers in a network.

Discuss the advantages and disadvantages to the school, staff and students of having the computers installed in a network.

SMTP and IMAP are email protocols.

Describe how SMTP and IMAP are used.

SMTP

IMAP

Describe how encryption can make the transmission of data more secure.

Blagging and phishing are social engineering techniques.

Describe blagging and phishing.

Viruses, trojans and spyware are forms of malware.

Describe how two of these forms of malware work.

Description

Description

Define the term database.

Explain what is meant by data inconsistency within a database.

Define the term foreign key.

A relational database is being developed to store information about actors and the films they have performed in.

The database contains three tables: Film, Performance and Actor.

Some of the contents of the tables are shown in Figure 8.

Figure 8

State the identifier of a field from the Actor table in Figure 8.

The film with the title Toy Story 3 has been entered incorrectly into the database and should have the title Toy Story 4.

Write the SQL to make this change.

Define the term cyber security.

A website wants to improve its cyber security procedures.

Explain how CAPTCHA and email confirmations could improve the security of the website.

CAPTCHA

Email confirmations