A preventive maintenance program that follows the philosophy of optimum parts replacement will have: a. No failures b. Minimal parts replacement costs c. Frequent maintenance operations d. Some failuresIf a component experiences infant mortality, but does not experience aging during its life then: a. A system overhaul leads to additional infant mortality possibilities b. A system overhaul leads to a decrease in infant mortality possibilities c. A system overhaul does not affect infant mortality possibilities d. The system will basically last forever