Gotham Company purchased a new machine on October 1, 2017, at a cost of $90,000. The company estimated that the machine has a salvage value of $8,000. The machine is expected to be used for 70,000 working hours during its 8-year life. Compute depreciation using the following methods in the year indicated. (a) Declining-balance using double the straight-line rate for 2017 and 2018. (b) Units-of-activity for 2017, assuming machine usage was 480 hours. (Round depreciation per unit to the nearest cent.)