E6.5 (LO 2), AP REI sells snowboards. Assume the following information relates to REI's purchases of snowboards during September. During the same month, 102 snowboards were sold. REI uses a periodic inventory system. Instructions b. Compute the cost of goods sold for the month using the FIFO, LIFO, and average-cost methods. (For average-cost, round the average unit cost to three decimal places.)