Sterling Steel Inc. purchased a new stamping machine at the beginning of the year at a cost of $720,000. The estimated residual value was $76,800. Assume that the estimated useful life was five years, and the estimated productive life of the machine was 268,000 units. Actual annual production was as follows: Year Units 1 78,000 2 66,000 3 30,000 4 58,000 5 36,000 Complete a separate depreciation schedule for each of the alternative methods. (Round your answers to the nearest dollar amount. Do not round your intermediate calculations. Omit the "$" sign in your response.) Straight-line. Units-of-production. . Double-declining-balance.