Question 1: Explain in your own words what data compression means and why it is useful.

Answer: Data compression is the process of reducing the size of data to save space or transmission time. It is useful because it makes data transfer faster and storage more efficient.

Question 2: Describe a situation where data compression might be used in everyday life.

Answer: Data compression is used when sending emails with large attachments, streaming videos online, or storing photos on a phone to save space.

Question 3: List two common methods of data compression and briefly explain each.

Answer: 1. Lossless compression: reduces file size without losing any data, allowing original data to be perfectly restored. 2. Lossy compression: reduces file size by removing some data, which may result in a loss of quality, used mainly for images and videos.

Question 4: A text file contains the sentence: 'The quick brown fox jumps over the lazy dog.' How might data compression reduce the size of this text?

Answer: Compression could replace repeated words or common phrases with shorter codes or use algorithms to find patterns and encode them more efficiently, reducing the overall size.

Question 5: Complete the truth table for an AND logic gate with two inputs, A and B. The outputs are in the column labeled 'Output'.

Answer: A | B | Output 0 | 0 | 0 0 | 1 | 0 1 | 0 | 0 1 | 1 | 1

Question 6: Draw a logic circuit that uses two AND gates and an OR gate to produce a specific output based on three inputs: A, B, and C. Label all gates and inputs clearly.

Answer: A correct sketch would show inputs A, B, and C feeding into the first AND gate, with A and B as inputs. The second AND gate takes B and C. The outputs of both AND gates feed into an OR gate, producing the final output. Labels should include the gate types and input/output points.

Question 7: Suppose you have a binary data sequence: 1011001. Describe one simple way to compress this data.

Answer: One way is to use run-length encoding, where sequences of repeated bits are replaced with a number indicating the count and the bit value, for example, '1 0 1 1 0 0 1' could be compressed to a shorter form if there are repeated bits.

Question 8: Sketch a bar chart to show how data size might decrease after compression compared to uncompressed data. Use labels for 'Uncompressed' and 'Compressed'.

Answer: A bar chart with two bars: one taller labeled 'Uncompressed' and a shorter one labeled 'Compressed', illustrating the reduction in size.

Question 9: Explain why lossy compression might be acceptable for images or videos but not for text files.

Answer: Lossy compression removes some data to reduce size, which is okay for images and videos because slight quality loss is not noticeable. However, for text files, losing data could make the information inaccurate or unreadable, so lossless compression is needed.

Question 10: Design a simple flowchart showing the process of compressing a file. Include at least three steps and brief descriptions.

Answer: The flowchart should include steps such as: 1. Input data, 2. Apply compression algorithm, 3. Output compressed data.