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.