Lance's Truck Stop purchased a new automatic truck washing machine for $135,000 at the first of last year. Lance estimates that the machine will last for 10 years at which time it can be sold for $35,000. Lance also estimated that a total of 50,000 trucks would use the machine before it was salvaged. During the first year 7,000 trucks were washed and the current year another 9,000 were washed