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Unit 4 Computer Architecture, Data, Communication and Applications

6 dot points across 6 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How are computing techniques such as artificial intelligence and machine learning applied, and what are their capabilities and limits?

Describe applications of computer science including artificial intelligence, machine learning, automation and modern computing applications.
A focused answer to WJEC A-Level Computer Science Unit 4 applications, covering artificial intelligence and machine learning, neural networks, expert systems, automation, and modern computing applications with their capabilities and limits.
12 min answer →

How are real numbers represented in floating point, and how is normalisation used to store them precisely?

Describe advanced data representation: floating-point numbers, normalisation, fixed-point, and the limits of representing real numbers.
A focused answer to WJEC A-Level Computer Science Unit 4 advanced data representation, covering floating-point form with mantissa and exponent, normalisation, fixed-point representation, and the precision and range limits of real numbers.
13 min answer →

How is modern computer architecture organised, and how do parallel processing and communication hardware improve performance?

Describe computer architecture in depth: processor design, parallel processing, peripherals, and the hardware and methods of communication.
A focused answer to WJEC A-Level Computer Science Unit 4 hardware and communication, covering processor architecture, the role of registers and buses, parallel processing, peripherals and storage, and communication hardware and methods.
13 min answer →

How is large-scale data organised in normalised relational databases, and how do big data and data warehousing extend this?

Describe the organisation and structure of data: relational databases, normalisation to third normal form, SQL, and big data and data warehousing.
A focused answer to WJEC A-Level Computer Science Unit 4 organisation of data, covering relational databases and keys, normalisation to first, second and third normal form, SQL, and big data and data warehousing.
13 min answer →

How does low-level assembly language work, and how do addressing modes let instructions reach their operands?

Describe low-level programming: machine code and assembly language, the instruction set, and addressing modes.
A focused answer to WJEC A-Level Computer Science Unit 4 low-level programming, covering machine code and assembly language, the instruction set, the structure of an instruction, and addressing modes such as immediate and direct.
12 min answer →

What are the ethical, legal, social and environmental impacts of computing, and how should they guide responsible use?

Evaluate the ethical, legal, social and environmental impacts of computer science and the relevant legislation.
A focused answer to WJEC A-Level Computer Science Unit 4 impact, covering the ethical, legal, social and environmental issues raised by computing, the relevant legislation, and how they guide responsible use.
12 min answer →