40. A machine cost $900,000 on April 1, 2020. Its estimated salvage value is $90,000 and its expected life is eight years. Required: A. Calculate the depreciation expense (to the nearest dollar) by each of the following methods, showing the amounts used. a. Straight-line for 2020 b. Double-declining balance for 2021 c. Sum-of-the-years'-digits for 2021 B. Which method would result in the smallest income amount for 2021