Beginning inventory, purchases, and sales data for “Commodity A” are as follows:

June 1:  Inventory 15 units at Birr 20.00

         3:  Sold 5 units

        12: Purchased 20 units at        22.50

        18: Sold15 units 

       30: Purchased10 units at        25.00

Required: If a periodic inventory system and perpetual inventory are used, determine separately  the cost of ending inventory and Cost of goods sold using:

FIFO

LIFO

AC (weighted average costing method)