need help with the double-declining method

Layton Company purchased tool sharpening equipment on October 1 for $108,000. The equipment was expected to have a useful life of three years, or 12,000 operating hours, and a residual value of $7,200. The equipment was used for 1,350 hours during Year 1, 4,200 hours in Year 2, 3,650 hours in Year 3, and 2,800 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-output method, and (c) the double-declining-balance method. Note: FOR DECLINING BALANCE ONLY, round the answer for each year to the nearest whole dollar