The problem presents a flowchart for selecting students for studying Information and Communication Technology, based on their marks in a test. The flowchart needs to be analyzed to determine the correct order of labels A, B, and C and identify the control structures used in it. Problem 29: Determine the correct order of labels A, B, C. The variable $st\_no$ represents the student number, with the total number of students equal to 50. Problem 30: Identify the control structures represented by the flowchart.

1. Problem Description

The problem presents a flowchart for selecting students for studying Information and Communication Technology, based on their marks in a test. The flowchart needs to be analyzed to determine the correct order of labels A, B, and C and identify the control structures used in it.

Problem 29: Determine the correct order of labels A, B, C. The variable $st\_no$ represents the student number, with the total number of students equal to

5

0.

Problem 30: Identify the control structures represented by the flowchart.

2. Solution Steps

Problem 29:

Step 1: Analyze label A. Since the program selects students for a test, it should check whether all 50 students have been evaluated or not. The condition at A should be whether $st\_no$ is within the range of the number of students being evaluated. If it is not, the process should end. Therefore, the check is $st\_no \le 50$ or $st\_no \ge 50$.

Step 2: Analyze the options given for A.

Option 1: $st\_no \le 50$

Option 2: $st\_no \ge 50$

Option 3: $st\_no \le 50$

Option 4: $st\_no \ge 50$

If the answer to A is 'No', then the process should terminate. This corresponds to the condition when $st\_no > 50$ in the case of option 1 and 3, or to the condition where $st\_no < 50$ when the answer is 'No' in the case of option 2 and

4.

If A is 'Yes', then the process should continue and the marks are read.

Since the starting value of $st\_no$ is 1, $st\_no > 50$ should mean the end of the program. Therefore the condition should be $st\_no \le 50$. Options 2 and 4 are incorrect.

Step 3: Analyze label B.

If the marks are greater than or equal to 50, the student is selected.

Therefore, B should output "You are selected". Options 1 and 3 are therefore "You are selected", "You are not selected".

Step 4: Analyze label C.

If the marks are less than 50, the student is not selected.

Therefore, C should output "You are not selected".

Step 5: Combine all the information.

A: $st\_no \le 50$

B: "You are selected"

C: "You are not selected"

This corresponds to option

1.

Problem 30:

Step 1: Identify the control structures.

The flowchart contains a decision structure (diamond shape) for checking if $st\_no \le 50$ which leads to an 'End' block if the condition is false. Another decision structure is whether `marks >= 50`. The flowchart also contains a loop where $st\_no$ is incremented, and the process repeats. A selection takes place whether or not the student obtains marks above

5

0. There is also a repetition occurring when the program iterates through all 50 students. So there is selection and repetition.

Step 2: Determine the order.

There is a selection for the marks. There is a repetition for students.

Thus, there is selection in repetition.

3. Final Answer

2

9. (1) $st\_no \le 50$, "You are selected", "You are not selected"

3

0. (2) Selection in Repetition