Fionnula Co. Uses a periodic inventory system Its records show the following for the month of May, in which 65 units were sold. Units Units Cost Total Cost May 1 Inventory 30 $ 8 $240 May15 Purchase 25 11 275 May24 Purchase 35 12 420 Totals 90 $935 Instructions: Compute the ending inventory at may 31 and cost of goods sold using the FIFO method and Average cost method.