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Sheffield Corp. sells a snowboard, EZslide, that is popular with snowboard enthusiasts. Below is information relating to Sheffield Corp's purchases of EZslide snowboards during September. During the same month, 100 EZslide snowboards were sold. Sheffield Corp. uses a periodic inventory system. Date Explanation Units Unit Cost Total Cost Sept. 1 Inventory - 10 $100 $1,000 Sept. 12 Purchases 103 4,635 Sept. 19 Purchases 5,200 Sept. 26 Purchases 105 2,100 Totals $12,935 (a) Compute the ending inventory at September 30 using the FIFO, LIFO and average-cost methods. (Round average cost per unit to 3 decimal places, e.g. 125.153 and final answers to 0 decimal places, e.g. 125.) FIFO LIFO AVERAGE-COST The ending inventory 3128 D 3047 3092 at September 30 (b) Compute the cost of goods sold at September 30 using the FIFO, LIFO and average-cost methods. (Round average cost per unit to 3 decimal places, e.g. 125.153 and final answers to 0 decimal places, e.g. 125.) FIFO LIFO AVERAGE-COST Cost of goods sold $ 10346 10427 10382