Perdue Company purchased equipment on April 1 for $49,890. The equipment was expected to have a useful life of three years, or 6,900 operating hours, and a residual value of $1,590. The equipment was used for 1,200 hours during Year 1, 2,400 hours in Year 2, 2,100 hours in Year 3, and 1,200 hours in Year 4.

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) the units-of-activity method, and (c) the double-declining-balance method.

Note: Round all final values for each depreciation method and each year to the nearest whole dollar.