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Exercise 6-05 a-b (Part Level Submission) (Video) Mary's Boards sells a snowboard, Xpert, that is popular with snowboard enthusiasts. Information relating to Mary's purchases of Xpert snowboards during September is shown below. During the same month, 121 Xpert snowboards were sold. Mary's uses a periodic inventory system. Date Explanation Units Total Cost Unit Cost $95 100 45 Sept. 1 Sept. 12 Sept. 19 Sept. 26 Inventory Purchases Purchases Purchases Totals $ 2,470 4,500 2,040 5,150 $14,160 103 141 (a) Compute the ending inventory at September 30 and cost of goods sold using the FIFO and LIFO methods. FIFO LIFO The ending inventory at September 30 Cost of goods sold