A machine cost $1,238,000 on April 1, 2020. Its estimated salvage value is $123,200 and its expected life is 4 years. Calculate the depreciation expense by straight-line for 2020. (Round answer to O decimal places. e.g. 5,275.) Depreciation expense $ Calculate the depreciation expense by double-declining balance for 2021. (Round answer to O decimal places, e.g. 5,275. Depreciation expense $ Calculate the depreciation expense by sum-of-the-years'-digits for-2021. (Round answer to O decimal places, eg. 5,275) Depreciation expense $ Which method would result in the smallest income amount for 2021