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, 120 Xpert snowboards were sold. Unit Date Explanation Units Cost Total Cost Sept. 1 Inventory Sept. 12 Purchases: Sept. 19 Purchases Sept. 26 Purchases 8 25 $90 $2,250 45 100 4,500 20 105 2,100 45 108 4,860 Totals 135 $13,710