[The following information applies to the questions displayed below.] Beck Inc. 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 2: Units Unit Cost Inventory, December 31, prior year 6,800 $ 8 For the current year: Purchase, March 5 18,800 6 Purchase, September 19 9,800 2 Sale ($30 each) 8,000 Sale ($32 each) 15,800 Operating expenses (excluding income tax expense) $ 398,000 Explain How to calculate ending inventory and other things .