Shamrock, Inc. sells a snowboard, EZslide, that is popular with snowboard enthusiasts. Below is information relating to Shamrock, Inc.'s purchases of EZslide snowboards during September. During the same month, 100 EZslide snowboards were sold. Date Sept. 1 Explanation Inventory Units 10 Unit Cost Total Cost $111 $1,110 Sept. 12 Purchases 46 114 5,244 Sept. 19 Purchases 49 115 5,635 Sept. 26 Purchases Totals 25 116 2,900 130 $14,889 Additional data regarding the company's sales of EZslide snowboards are provided below. Assume that Shamrock, Inc. uses a perpetual inventory system. Date Units Sept. 5 Sept. 16 Sale Sale 8 47 Sept. 29 Sale 45 100 Totals (a)