Kimberly's Boards sells a snowboard, Xpert, that is popular with snowboard enthusiasts. Information relating to Kimberly's purchases of Xpert snowboards during September is shown below. During the same month, 124 Xpert snowboards were sold. Kimberly's uses a periodic inventory system. (a) Compute the ending inventory at September 30 and cost of goods sold using the FIFO and LIFO methods