Riverbed Inc. uses a periodic inventory system. Its records show the following for the month of May, in which 80 units were sold. w Date Units Unit Cost Total Cost Explanation Inventory 31 $8 $ 248 May 1 May 15 Purchase 23 9 207 May 24 Purchase 41 10 410 Total 95 $ 865 Calculate the cost of goods sold and the ending inventory at May 31 using the average cost formula. (Round average cost to 3 decimal places, eg. 5.252 and round final answer to 2 decimal places, eg 5.25.) Cost of goods sold $ 728.4 Ending inventory $