Duluth Ranch, Incorporated purchased a machine on January 1, 2021. The cost of the machine was $44,000. Its estimated residual value was $14,000 at the end of an estimated 5-year life. The company expects to produce a total of 20,000 units. The company produced 1,600 units in 2021 and 2,050 units in 2022. Required: a. Calculate depreciation expense for 2021 and 2022 using the straight-line method. b. Calculate the depreciation expense for 2021 and 2022 using the units-of-production method. c. Calculate depreciation expense for 2021 through 2025 using the double-declining balance method.