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, prior year 2,000 $ 5 For the current year: Purchase, March 21 5,000 6 Purchase, August 1 3,000 8 Inventory, December 31, current year 4,000.

Compute ending inventory and cost of goods sold for the current year under FIFO, LIFO, and average cost inventory costing methods.