1. Silverman Company purchased machinery for $162,000 on January 1, 2010. It is estimated that the machinery will have a useful life of 20 years, salvage value of $15,000, production of 84,000 units, and working hours of 42,000. During 2010 the company uses the machinery for 14,300 hours, and the machinery produces 20,000 units. Compute depreciation under the straight-line, units-of-output, working hours, sum-of-the-years'-digits, and double-declining balance methods.