1. Basic IF-ELSE

Write a COBOL program that accepts an age as input and displays:

• "Adult" if age is 18 or above
• "Minor" otherwise

2. Nested IF

Write a COBOL program that accepts marks of a student and displays grades as follows:

• Marks >= 90: Grade A
• Marks >= 75: Grade B
• Marks >= 60: Grade C
• Marks < 60: Grade D

3. IF with Arithmetic Operations

Write a COBOL program to accept a salary amount and add a bonus based on the following conditions:

• If salary > 50000, add 10% bonus
• If salary > 30000, add 7% bonus
• Otherwise, add 5% bonus
• Display the updated salary.