Question 1: Define a variable in programming and explain its purpose.

Answer: A variable is a named storage location in a program that holds data which can be changed during execution. It allows programmers to store, modify, and retrieve data dynamically.

Question 2: Write a simple line of code in a programming language of your choice that declares an integer variable named 'score' and assigns it the value 10.

Answer: int score = 10; (in Java or C++) or score = 10; (in Python, with prior declaration)

Question 3: Explain the difference between a variable's data type and its value.

Answer: A variable's data type defines what kind of data it can hold (e.g., integer, string, boolean), while its value is the specific data stored in the variable at a given time.

Question 4: Given the following pseudo-code: 'Set total to 0; For each number from 1 to 5, add the number to total.' What is the final value of 'total'?

Answer: The final value of 'total' is 15, because 1 + 2 + 3 + 4 + 5 = 15.

Question 5: Complete the truth table for an AND gate with inputs A and B. Fill in the output column.

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

Question 6: Complete the truth table for an OR gate with inputs A and B. Fill in the output column.

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

Question 7: Draw a logic circuit that uses AND, OR, and NOT gates to produce an output 'Z' that is true only when either 'A' is true and 'B' is false, or 'C' is true.

Answer: The correct sketch should show: an AND gate with inputs A and NOT B (the NOT gate inverts B), an OR gate that takes the output of the AND gate and the input C, and finally, the output Z from the OR gate.

Question 8: Sketch a flowchart diagram to represent a program that asks for the user's age and displays a message if the user is 18 or older.

Answer: The sketch should include: a start symbol, an input symbol labeled 'Enter age', a decision symbol asking 'Is age >= 18?', with 'Yes' leading to a process symbol 'Display message: You are an adult', and 'No' leading to 'Display message: You are a minor', then an end symbol.

Question 9: Describe how variables can be used to store user input in a program.

Answer: Variables can store data received from the user through input functions or prompts. When the user enters information, it is assigned to a variable, allowing the program to process or respond based on that data.

Question 10: If a variable 'counter' starts at 0 and is incremented by 1 inside a loop that runs 10 times, what is the value of 'counter' after the loop completes?

Answer: The value of 'counter' will be 10 after the loop completes.

Question 11: Explain the importance of using descriptive variable names in programming.

Answer: Using descriptive variable names makes code easier to read, understand, and maintain. It helps programmers quickly identify the purpose of a variable without needing extra comments.