A company just starting business made the following four inventory purchases in June: June 1 100 units $ 400 June 10 200 units 850 June 15 200 units 900 June 28 100 units 500 $2.115 A physical count of merchandise inventory on June 30 reveals that there are 100 units remaining in ending inventory. The inventory method which results in the highest gross profit for June is: O the FIFO method O the LIFO method O the weighted average unit cost method, O not determinable