14-81 A small research device can be purchased for $10,000 and depreciated by 5-year MACRS depre- ciation. The net benefits from the device, before deducting depreciation, are $2500 at the end of the first year and increasing $1250 per year after that, until the device is hauled to the junkyard at the end of 10 years. During the 10-year period there will be an inflation rate f of 7%. This profitable corporation has a 40% combined federal and state income tax rate. If it requires a real 15% after-tax rate of return on its investment, should the device be purchased