Your tractor broke down and was in the shop for 2  days. Mechanics worked on it for 15.4 hours at $45 per hour. They replaced $857.46 worth of parts. You lost $12 per hour by not having the use of the tractor. You normally work a 14-hour day. 

a. How much did the labor cost? 

b. What was the repair bill (labor and parts)? 

c. How much did you lose by not having the use of your tractor?

d. What did the breakdown actually cost?