The total maintenance cost curve $($preventive maintenance cost plus breakdown and repair cost$)$

Multiple Choice

starts low, increases rapidly, and then drops back down as the number of preventive maintenances increases.

starts high, drops gradually, but then goes back up as the number of preventive maintenances increases.

slopes down as the number of preventive maintenances increases.

slopes up as the number of preventive maintenances increases.

remains relatively flat as the number of preventive maintenances increases.