Equipment with a cost of $556,100 has an estimated residual value of $50,600, has an estimated usefu. life of 15 years, and is aepreciated by the straight-line method. a. Determine the amount of the annual depreciation. b. Determine the book value at the end of the 8 full years of use. c. Assuming that at the start of the year 9 the remaining life is estimated to be 13 years and the residual value is estimated to be $43,400, determine the depreciation expense for each of the remaining 13 years