On October 6, 2020, Western Farms Co. traded in an old tractor for a new one, receiving a $70,000 trade-in allowance and paying the remaining $171,000 in cash. The old tractor cost $204,000, and straight-line depreciation of $112,000 had been recorded as of October 6, 2020. Assume the fair value of the new tractor was equal to the trade-in allowance of the old tractor plus the cash paid. Required: a. What was the book value of the old tractor? Book value b. What is the gain or loss on the exchange?