1: A firm purchased equipment for $162,000 on January 1, 2020. It is estimated that the equipment will have a useful life of 20 years, residual value of $15,000, production of 84,000 units, and working hours of 42,000. During 2020, the company uses the equipment for 14,300 hours, and the equipment produces 20,000 units. Compute depreciation under the straight-line, units of production, working hours and double-declining-balance methods for 2020