Three different companies each purchased trucks on January 1, 2018, for $76,000. Each truck was expected to last four years or 250,000 miles. Salvage value was estimated to be $6,000. All three trucks were driven 81,000 miles in 2018, 55,000 miles in 2019, 46,000 miles in 2020, and 71,000 miles in 2021. Each of the three companies earned $65,000 of cash revenue during each of the four years. Company A uses straight-line depreciation, company B uses double-declining-balance depreciation, and company C uses units-of-production depreciation. Answer each of the following questions. Ignore the effects of income taxes. d-1. Calculate the retained earnings on the December 31, 2021, balance sheet?