Sheffield Corp. sells a snowboard, WhiteOut, that is popular with snowboard enthusiasts. Presented below is information relating to Sheffield Corp.'s purchases of White Out snowboards during September. During the same month, 97 White Out snowboards were sold at $170 each. Sheffield Corp. uses a periodic inventory system. Date Explanation Units Unit Cost Total Cost Sept. 1 Inventory 20 $100 $2,000 Sept. 12 Purchases 36 106 3,816 Sept. 19 Purchases 19 110 2,090 Sept. 26 Purchases 40 112 4,480 Totals 115 $12,386