OZ Company purchased new machinery equipment on July 1, 20X6, for $15,660. The equipment was expected to have a usefu of three years, or 18,825 operating hours, and a residual value of $600. The equipment was used for 3,750 hours during 2 7,500 hours in 20X7, 5,000 hours in 20X8, and 2,575 hours in 20X9. Requirements Determine the amount of depreciation expense for the years ended December 31, 20X6, 20X7, 20X8, and 20X9, by (a) the straight-line method, (b) the units-of-production method, and (c) the double-declining-balance method. Round to the nearest dollar