At the beginning of the year, palermo brothers, inc., purchased a new plastic water bottle making machine at a cost of $56,000. the estimated residual value was $6,000. assume that the estimated useful life was four years, and the estimated productive life of the machine was 500,000 units. actual annual production was as follows: year units1 122 93 114 8required: 1. complete a separate depreciation schedule for each of the alternative methods. round your answers to the nearest dollar. a. straight-line. b. units-of-production. c. double-declining-balanceyear computation depreciation expense accumulated depreciation net book value2. assuming that the machine was used directly in the production of one of the products that the company manufactures and sells, what factors might management consider in selecting a preferable depreciation method in conformity with the expense principle?