Martinez Inc. uses a periodic inventory system. Its records show the following for the month of May, in which 72 units were sold. Date Explanation Units Unit Cost Total Cost May 1 Inventory 32 $9 $288 May 15 Purchase 223 10 230 May 24 Purchase 40 11 440 Total 95 $958 (a) Calculate the Cost of goods sold and the ending inventory at May 31 using the FIFO formula. Cost of goods sold Ending inventory $ LA $