E8-14 [This is a variation of Exercise 8-13 modified to focus on the perpetual inventory system and alternative cost flow methods.] Altira Corporation uses a perpetual inventory system. The following transactions affected its merchandise inventory during the month of August 2011: Aug 1 Inventory on hand - 2,000 units; cost $6.10 each. Purchased 10,000 units for $5.50 each Aug 8 Aug 14 Sold 8,000 units for $12.00 each Aug 18 Purchased 6,000 units for $5.00 each Aug 25 Sold 7,000 units for $11.00 each.