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Periodic inventory by three methods; cost of goods sold The units of an item available for sale during the year were as follows: Jan. 1 Inventory 40 units at $116 Mar. 10 Purchase 60 units at $128 Purchase 30 units at $134 Aug. 30 Dec. 12 Purchase 70 units at $138 There are 80 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the ending inventory cost and the cost of goods sold by three methods. Round interim calculations to one decimal and final answers to the nearest whole dollar. Cost of Ending Inventory and cost of Goods Sold Inventory Method Ending Inventory Cost of Goods Sold First-in, first-out (FIFO) $ Last-in, first-out (LIFO) Weighted average cost