Units-of-activity Depredation A truck acquired at a cost of $270,000 has an estimated residual value of $16,850, has an estimated useful life of 61,000 miles, and was driven 6,100 miles during the year. Determine the following. If required, round your and for the depreuation rate to two decimal places. (a) The depreciable cost (b) The depreciation rate (c) The units of activity depreciation for the year per mile