Davidson Electronics has the following: Units Unit Cost Inventory, Jan. 1 5,000 $8 Purchase, April 2 15,000 10 Purchase, Aug. 28 20,000 12 If Davidson has 7,000 units on hand at December 31, how much is the cost of ending inventory under the average-cost method in a periodic inventory system? O $84,000 O $75,250 O $56,000 O $70,000