A firm with a 30% marginal tax rate buys equipment for $150,000 with a salvage value of $20,000 and an expected useful life of 10 years. If the firm decides to sell the equipment after 5 years for $75,000, calculate the after-tax gain/loss on the sale of the equipment using the MACRS depreciation method. a) \$19,710 gain b) $13,797 loss c) \$13,797 gain d) $19,710 loss