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E6-4 Mather sells a snowboard, Ezslide, that is popular with snowboard enthusiasts Below is relating to Mather's purchases of Ezslide snowboards during tember. During the same month, 102 Ezslide boards were sold. Mather uses a periodic inventory system. Date Explanation Units Unit cost Total Cost Sept. 1 Inventory $100 1,200 Sept. 12 Purchases 45 103 4,635 Sept. 19 Purchases 104 5,200 Sept. 26 Purchases 2,100 Totals 127 $13,135