Rottino Company purchased a new machine on October 1, 2017, at a cost of $138,000. The comapny estimated that the machine will have a salvage of $22,000. The machine is expected to be used for 10,000 working hours during its 4-year life.

1. Compute the depreciation expense under straight-line method for 2017.

2. Compute the depreciation expense under units-of-activity for 2017, assuming machine usage was 1,500 hours.

3. Compute the depreciation expense under declining-balance using double the straight-line rate for 2017 and 2018.