Hannibal owns a farm.  He purchases a tractor in 2014 at a cost of $25,000.  Because 2014 is a bad year, he does not deduct any depreciation on the tractor in 2014.  He sells the tractor in 2018 for $16,000. He takes straight-line depreciation on the tractor of $12,500 for the years 2015 to 2018. The total allowable straight-line depreciation for the tractor for 2014 to 2018 is $15,000.  What is Hannibal's gain or loss on the sale of the tractor? Explain