Revision of Depreciation A building with a cost of $540,000 has an estimated residual value of $108,000, has an estimated useful life of 18 years, and is depreciated by the straight-line method. a. What is the amount of the annual depreciation? $1 b. What is the book value at the end of the tenth year of use? $1 c. If at the start of the eleventh year it is estimated that the remaining life is 10 years and that the residual value is $20,000, what is the depreciation expense for each of the remaining 10 years