What is the expected after-tax cash flow from selling a piece of equipment if Litchfield Design purchases the equipment today for 70,000 dollars, the tax rate is 20 percent, the equipment is sold in 3 years for 9,000 dollars, and MACRS depreciation is used where the depreciation rates in years 1, 2, 3, 4, and 5 are 34 percent, 28 percent, 23 percent, 10 percent, and 5 percent, respectively?