On January 2, 2018, Country Lumber installed a computerized machine in its factory at a cost of $168,000. The machine's useful life was estimated at four years or a total of 190,000 units with a $35,000 trade-in value. Country Lumber's year-end is December 31. Calculate depreciation for each year of the machine's estimated useful life under each of the following methods a. Straight-line b. Double-declining-balance c. Units-of-production, assuming actual units produced were: Year Units 2018 39,900 2019 43,550 2020 54,200 2021 72,000 Year a. Straight- b. Double-Declining- Line Balance c. Units of Production 2018 S 33,250 $ 84,000 $ 27.930 2019 $ 9 33,250 $ 42,000 $ 30,485 2020 S 33,250 $ 21,000 $ 37,940 2021 $ 33,250 $ 10,500 $ 50.400 Total $ 133.000 $ 157 500 S 146.755