Robert Parish Corporation purchased a new machine for its assembly process on January 1, 2014. The cost of this machine was $855,000. The company estimated that the machine would have a salvage value of $35,000 at the end of its service life. Its life is estimated at 4 years, and its working hours are estimated at 60,000 hours. Year-end is December 31.

Compute the depreciation expense under the following methods and complete the depreciation schedules below.

(a)	Straight-line depreciation.
(b)	Activity method, assuming that machine usage was 20,000 hours for 2014; 19,000 hours for 2015; 13,000 hours for 2016 and 8,000 hours for 2017.
(c)	Sum-of-the-years'-digits.
(d)	Double-declining-balance.