Pharmacy Co exchanges a patent with a cost of $50,000,$ accumulated amortization of $10,000$ and a market value of $80,000$ for a different patent with a book value of $80,000,$ a market value of $25,000.$ Assuming this has commercial substance, what amount or gain or loss should be booked by Pharmacy Co$?(3$ points$)$

Gain$/$loss of $$0$

Gain of $$40,000$

Loss of $$15,000$

Loss of $$55,000$