Equipment acquired on January 8, 20Y1, at a cost of $712,500, has an estimated useful life of 18 years and an estimated residual value of $128,250. a. What was the annual amount of depreciation for the years 20Y1, 20Y2, and 20Y3, using the straight-line method of depreciation? Round annual depreciation to the nearest dollar and use this amount in your follow-on calculations. Depreciation expense 20Y1 $ 20Y2 $ 20Y3 $ b. What was the book value of the equipment on January 1, 20Y4? $