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A factory machine was purchased for $175,000 on January 1, 2020. It was estimated that it would have a $35,000 residual value at the end of its 5-year useful life. It was also estimated that the machine would be run 40,000 hours in the 5 years. The company ran the machine for 4,000 actual hours in 2020. If the company uses the units-of-activity method of depreciation, the amount of depreciation expense for 2020 would be A. $3,500. B. $14,000. C. $35,000. D. None of the above