Stanton sells a surfboard, Flash, that is popular with surfing enthusiasts. Below is information relating to the company's purchases of Flash surfboard during July. During the same month, 88 Flash surfboards were sold. Stanton uses a periodic inventory system.(E6-4B) Date July 1 July 12 July 19 July 26 Explanation Inventory Purchases Purchases Purchases Totals Units 20 35 15 40 110 Unit Cost $ 120 125 128 130 Total Cost $ 2,400 4,375 1,920 5,200 $13,895 (a) Compute the ending inventory at September 30 and cost of goods sold using the FIFO,LIFO & Average Cost methods. Prove the amount allocated to cost of goods sold under each method. (b) For both FIFO and LIFO, calculate the sum of ending inventory and cost of goods sold. What do you notice about the answers you found for each method