(15) 2. ABC Construction must replace a number of its concrete mixer trucks with new trucks. It has received two bids and has evaluated closely the performance characteristics of the various trucks. The truck A, which costs $77,000, is top-of-the-line equipment. The truck has a life of eight years, assuming that the engine is rebuilt in the fifth year Maintenance costs of $3,000 a year are expected in the first four years, followed by total maintenance and rebuilding costs of $12,000 in the fifth year, During the last three years, maintenance costs are expected to be $4,000 a year. At the end of eight years the truck will have an estimated scrap value of $10,000