AgriGrow is to purchase a tractor for over-the-road hauling for \($90,000.\) It is expected to be of use to the company for 6 years, after which it will be salvaged for \($4,000.\) Transportation cost savings are expected to be \($170,000\) per year; however, the cost of drivers is expected to be \($70,000\) per year, and operating expenses are expected to be \($63,000\) per year, including fuel, maintenance, insurance, and the like. The company’s marginal tax rate is 40 percent, and MARR is 10 percent on after-tax cash flows. Suppose that, to AgriGrow’s surprise, they actually dispose of the tractor at the end of the fourth tax year for \($6,000.\) Develop tables using a spreadsheet to determine the ATCF for each year and the after-tax PW, AW, IRR, and ERR after only 4 years.

a. Use straight-line depreciation (no half-year convention).

b. Use MACRS-GDS and state the appropriate property class.

c. Use double declining balance depreciation (no half-year convention, no switching).