Answer:
2. To loosen and tighten bolts with a hexagonal (six-sided) head, use a hex driver
3. Do not use the hex driver which is too big for the bolt you are using.
4. It is necessary keeping computers clean inside and out is a vital part of a maintenance program,
5. Dirt can't cause problems with the physical operation of fans, buttons, and other mechanical components. 6. Damaged or defective equipments for cleaning the house and/tools should be tagged and removed from service
7. Most manufacturers can provide maintenance schedules for their equipment