Suppose that Amazon uses a periodic inventory system and reports the following for the month of June: Unit Date Explanation Units Cost Total Cost June 1 Inventory 360 $8 $2,880 12 Purchase 840 9 7,560 23 Purchase 1,200 10 12,000 30 Inventory 448 (a) Compute the cost of the ending inventory and the cost of goods sold under (1) FIFO, (2) LIFO, and (3) average-cost. (Round average cost per unit to 2 decimal places, e.g. 5.25 and final answers to O decimal places, e.g. 2,520.) FIFO Ending inventory $ Cost of goods sold $ LIFO AVERAGE-COST $ $ $