A company has the following: Dec. 1 Beginning inventory 15 units at $60 Dec. 5 Purchases 90 units at $65 Dec. 14 Sale 50 units Dec. 21 Purchases 45 units at $68 Dec. 30 Sale 30 units Assuming that a perpetual inventory system is used, what is the cost of goods sold on a LIFO basis for December? .