The cost of equipment purchased by Whispering, Inc., on April 1, 2020, is $119,000. It is estimated that the machine will have a $5,000 salvage value at the end of its service life. Its service life is estimated at 6 years; its total working hours are estimated at 28,500; and its total production is estimated at 456,000 units. During 2020, the machine was operated 3,500 hours and produced 40,000 units. During 2021, the machine was operated 4,700 hours and produced 54,000 units. Compute depreciation expense on the machine for the year ending December 31, 2020, and the year ending December 31, 2021, using the following methods. (Round depreciation per unit to 2 decimal places, e.g. 15.25 and final answers to 0 decimal places, e.g. 45,892.)

a) Straight Line Method for year 2020 and 2021

b) Sum-of-the-years'-digit 2020 and 2021

c) Double declining balance(twice the straight-line rate)