Can someone explain how to fill this out?

uno poms E7-5 Calculating Ending Inventory and Cost of Goods Sold Under FIFO, LIFO, and Average Cost L07-2 Penn Company uses a periodic inventory system. At the end of the annual accounting period, December 31 of the current year the accounting records provided the following information for product 1 Units Unit Cost Inventory, December 31 pror year 3,000 $10.00 For the current year Purchase, March 21 6,000 11.00 Purchase, August 1 4.000 4.00 Inventory, December 31. Current year 7000 Required: Compute ending inventory and cost of goods sold for the current year under FIFO, LIFO, and average cost inventory costing methods (Do not round "Average cost per unit" and round your final answers to nearest whole dollar amount.) FIFO LIFO Average Cost Ending inventory Cost of goods sold