Periodic Inventory by Three Methods; Cost of Merchandise Sold The units of an item available for sale during the year were as follows: Jan. 1 Inventory 42 units @ $720 Mar. 10 Purchase 58 units @ $780 Aug. 30 Purchase 20 units @ $816 Dec. 12 Purchase 30 units @ $840 There are 48 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the inventory cost and the cost of merchandise sold by three methods. FiFo LIFO Weighted average cost