Question 1: List three different sorting algorithms and briefly describe how each one sorts data.

Answer: Common sorting algorithms include Bubble Sort, Selection Sort, and Insertion Sort. Bubble Sort repeatedly swaps adjacent elements if they are in the wrong order. Selection Sort finds the smallest element and places it at the beginning, then repeats for the remaining list. Insertion Sort builds a sorted list by inserting each new element into its correct position within the sorted part.

Question 2: Explain what is meant by the term 'stable sort' and give an example of a situation where stability is important.

Answer: A stable sort maintains the relative order of records with equal keys. For example, when sorting a list of students by grade, if two students have the same grade, their original order should remain after sorting. This is important when multiple sorting criteria are used sequentially.

Question 3: Describe the main difference between Merge Sort and Quick Sort.

Answer: Merge Sort divides the list into halves, sorts each half recursively, and then merges the sorted halves. Quick Sort selects a pivot, partitions the list into elements less than and greater than the pivot, then sorts each partition recursively. Merge Sort guarantees a consistent performance, while Quick Sort is generally faster on average but can perform poorly with certain data arrangements.

Question 4: Complete the truth table below for the AND logic gate.

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

Question 5: Complete the truth table below for the OR logic gate.

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

Question 6: Draw a logic circuit that represents the expression: (A AND B) OR C. Use symbols for AND, OR gates, and label each input and gate.

Answer: A correct sketch would show two inputs labeled A and B feeding into an AND gate, with its output and input C feeding into an OR gate. The final output is from the OR gate. The diagram should clearly label each component and connection.

Question 7: Sketch a flowchart that shows the steps to sort a list of numbers in ascending order using any sorting method. Include decision points and processes.

Answer: A proper flowchart would start with 'Start', then 'Select a sorting method', followed by iterative steps: comparing adjacent elements, swapping if necessary, checking if list is sorted, and repeating until sorted. End with 'Output sorted list' and 'Stop'.

Question 8: Explain in your own words how the Bubble Sort algorithm works.

Answer: Bubble Sort compares each pair of adjacent items in the list. If they are in the wrong order, it swaps them. This process repeats for each pair in the list, repeatedly passing through the list until no swaps are needed, meaning the list is sorted.

Question 9: Identify the main advantage and disadvantage of using Quick Sort.

Answer: The main advantage of Quick Sort is that it is generally faster on average and uses less memory than other algorithms. The main disadvantage is that its worst-case performance is poor (O(n²)) when the list is already nearly sorted or contains many duplicate elements.

Question 10: Describe a scenario where a stable sorting algorithm would be necessary in a computer program.

Answer: A scenario is sorting a list of employees first by department and then by hire date. If the sorting by hire date is stable, the original order within each department is preserved after sorting, maintaining logical grouping.