i. System Maintenance: It refers to the ongoing process of updating, fixing, and improving a system after it has been implemented to ensure its continuous and effective operation.

ii. Three Reasons for Maintaining a System:

1. To correct unforeseen problems that arise during system operation.
2. To ensure that the system continues to meet its original objectives and functions as intended.
3. To accommodate changes in business processes or requirements that were not anticipated during initial system development.

iii. Three Reasons for Adaptive Maintenance:

1. The system’s user requirements may have changed or were not clearly defined during its design.
2. The environment in which the system operates may have changed, requiring adjustments.
3. The system may have grown beyond the limits originally anticipated, necessitating modifications.