(a)
Object-Oriented Programming (OOP) is a programming paradigm based on the concept of “objects,” which are instances of classes containing both data and methods.

• Examples: Java, Python

(b)
Advantages of OOP as a 5GL:

1. Code Reusability: OOP allows developers to reuse code, reducing redundancy.
2. Modularity: Programs can be divided into smaller, more manageable sections.
3. Easy Maintenance: OOP enhances maintainability through abstraction and encapsulation.

(c)
System Changeover Methods:

1. Direct Changeover: The old system is completely replaced by the new system in one go.
2. Parallel Running: Both the old and new systems run simultaneously for a period to ensure the new system works correctly.
3. Phased Implementation: The new system is introduced in stages or modules.
4. Pilot Running: The new system is implemented in a small part of the organization to test its effectiveness before full-scale implementation.

(d)
An IP address (Internet Protocol address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication.