Longmire & Sons made sales on credit to Alderman Sports totaling $$500,000$ on April $18.$ The cost of the goods sold is $$400,000.$ Longmire estimates $3\%$ of its sales to Alderman may be returned. On May $22,$ $$9,000$ worth of goods $($with a cost of $$7,200)$ are returned by Alderman. Longmire uses a periodic inventory system.