Perdue Company purchased equipment on April 1 for $90,180. The equipment was expected to have a useful life of three years, or 6,480 operating hours, and a residual value of $2,700. The equipment was used for 1,200 hours during Year 1,2,300 hours in Year 2, 1,900 hours in Year 3, and 1,080 hours in Year 4. Required: Determine the amount of depreciation expense for the years ended December 31, Year 1, Year 2, Year 3, and Year 4, by (a) the straight-line method, (b) units-of-activity method, and (c) the double-declining-balance method. Note: FOR DECLINING BALANCE ONLY, round the multiplier to four decimal places. Then round the answer for each year to the nearest whole dollar. a. Straight-line method Year Amount Year 1 Year 2 Year 3 Year 4 b. Units-of-activity method Year Amount Year 1 Year 2 mon Year 3 Year 4 c. Double-declining balance method Year Amount Year 1 c. Double-declining-balance method Year Amount Year 1 Year 2 Year 3 Year 4