4 Dougan Company purchased equipment on January 1, 2017 for $90,000. It is estimated that the equipment will have a $5,000 salvage value at the end of its 5-year useful life. It is also estimated that the equipment will produce 100,000 units over its 5-year life. Answer the following independent questions. Compute the amount of depreciation expense for the year ended December 31, 2017, using the straight-line method of depreciation. Straight-line method per year $ If 16,000 units of product are produced in 2017 and 24,000 units are produced in 2018, what is the book value of the equipment at December 31, 2018? The company uses the units-of-activity depreciation method. Book value If the company uses the double-declining-balance method of depreciation, what is the balance of the Accumulated Depreciation-Equipment account at December 31, 2019? Accumulated Depreciation-Equipment