Revision of depreciation

Equipment with a cost of $791,000 has an estimated residual value of $91,000, has an estimated useful life of 40 years, and is depreciated by the straight-line method.

a. Determine the amount of the annual depreciation. $

b. Determine the book value after 17 full years of use. $

c. Assuming that at the start of the year 18 the remaining life is estimated to be 30 years and the residual value is estimated to be $91,500, determine the depreciation expense for each of the remaining 30 years.$