Hi, I need help with this question:

Three different companies each purchased trucks on January 1, 2018, for $82,000. 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 79,000 miles in 2018, 56,000 miles in 2019, 51,000 miles in 2020, and 71,000 miles in 2021. Each of the three companies earned $71,000 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.

Calculate the retained earnings on the December 31, 2021, balance sheet?

	Retained earnings
company A
company B
company C

Please, help!!