THIS A UML QUESTIONS PLEASE I NEED A DETAILED ANSWERS AND DIAGRAMS, THANKS

Use case 4: Equipment maintenance

1. The owner selects the equipment to be repaired and fills in the repair form.

2. The status of the equipment is changed to repair.

3. The owner contacts the manufacturer for on-site repair.

4. After the repair is completed, the owner fills in the repair result form, changes the status of the equipment back and records comments.