Sandhill Co. sells a snowboard, EZslide, that is popular with snowboard enthusiasts. Below is information relating to Sandhill Co.'s purchases of EZslide snowboards during September. During the same month, 101 EZslide snowboards were sold. Sandhill Co. uses a periodic inventory system. Date Explanation Units Unit Cost Total Cost Sept. 1 Inventory 10 $112 $1,120 Sept. 12 Purchases 50 115 5,750 Sept. 19 Purchases 57 116 6,612 Sept. 26 Purchases 21 117 2,457 Totals 138 $15,939 (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, eg. 125.153 and final answers to O decimal places, eg. 125.) The ending inventory at September 30 1 FIFO LIFO AVERAGE-COST decimal places, eg. 125.153 and final answers to 0 decimal places, e.g. 125.) The ending inventory at September 30 FIFO LIFO AVERAGE-COST (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 O decimal places, e.g. 125.) Cost of goods sold $ FIFO LIFO AVERAGE-COST