On October $6,2023,$ Western Farms Co$.$ traded in an old tractor for a new one, receiving a $$64,000$ trade$-$in allowance and paying the remaining $$168,000$ in cash. The old tractor cost $$198,000,$ and straight$-$line depreciation of $$109,000$ had been recorded as of October $6,2023.$ 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?

b$.$ What is the gain or loss on the exchange?

c$.$ What amount should be debited to the new Tractor account?

d$.$ Record the exchange.