The accounting records of Skysong, Inc. show the following data. (a) Your answer has been saved. See score details after the due date. Calculate average unit cost. (Round answer to 3 decimal places, eg. 5.125.) Average unit cost $ per ufsit Determine cost of goods sold during the period under a periodic inventory system using the FIFO method, the LIFO method, and the average-cost method. (Round answers to O decimal places, eg. 125.)