Question 1: Explain in your own words what data compression is and why it is important in computer science.

Answer: Data compression reduces the size of data to save storage space and improve transmission speed, making data easier to manage and faster to send or receive.

Question 2: List two common types of data compression and give an example of each.

Answer: Lossless compression (e.g., ZIP files), which preserves all original data; Lossy compression (e.g., JPEG images), which sacrifices some data for higher compression.

Question 3: Describe a scenario where lossless compression would be preferred over lossy compression.

Answer: When compressing text files or source code, where losing data could cause errors or corruption.

Question 4: Complete the truth table for an AND logic gate with inputs A and B, and output C.

Answer: A | B | C 0 | 0 | 0 0 | 1 | 0 1 | 0 | 0 1 | 1 | 1

Question 5: Draw a logic circuit that uses two AND gates and one OR gate to combine three inputs, A, B, and C, so that the output is true when at least two inputs are true.

Answer: The sketch should show two AND gates: one with inputs A and B, and the other with inputs B and C. The outputs of these gates feed into an OR gate, which produces the final output.

Question 6: Describe how a logic circuit could be used to detect patterns in data during compression.

Answer: A logic circuit can identify repeating patterns or specific sequences in data, allowing the system to replace them with shorter codes, thus reducing data size.

Question 7: Sketch a simple schematic showing how a NOT gate could be used to invert a binary signal in a compression algorithm.

Answer: The sketch should show a single input wire labeled 'A' entering a NOT gate, with the output labeled 'NOT A'.

Question 8: Explain the concept of entropy in data compression and how it relates to the efficiency of compression algorithms.

Answer: Entropy measures the amount of unpredictability in data; lower entropy means data has repetitive patterns and can be compressed more effectively, while high entropy data is less compressible.

Question 9: Describe one advantage and one disadvantage of using lossy compression.

Answer: Advantage: Higher compression ratios, saving more space. Disadvantage: Loss of some original data, which may reduce quality.

Question 10: Complete the truth table for an OR logic gate with inputs A and B, and output C.

Answer: A | B | C 0 | 0 | 0 0 | 1 | 1 1 | 0 | 1 1 | 1 | 1