View Policies Current Attempt in Progress REI sells snowboards. Assume the following information relates to REI's purchases of snowboards during September. During the same month, 102 snowboards were sold. REI uses a periodic inventory system. Date Explanation Units Unit Cost Total Cost Sept. 1 Inventory 12 $102 $1,224 Sept. 12 Purchases 45 105 4,725 Sept. 19 Purchases 57 106 6,042 Sept. 26 Purchases 24 24 107 2.568 Totals 138. $14,559