viary Corp., a sole proprietorship, sold a building for $600,000. Aviary received a down payment of $120,000 as well as annual principal payments of $120,000 for each of the subsequent four years. Aviary purchased the building for $500,000 and claimed depreciation of $80,000. What amount of gain should Aviary report in the year of sale using the installment method? $180,000 $120,000