explain the answers

Shown below is activity for one of the products of Denver Office Equipment: January 1 balance, 580 units @ $60 per unit $34,800 Purchases: January 580 units @ $65 per unit 10: January 1,040 units @ $68 per unit 20: Sales: January 900 units 12: January 780 units 28: Required: Compute the January 31 ending inventory and cost of goods sold for January, assuming Denver uses average cost and a perpetual inventory system. (Do not round intermediate calculations. Round your final answers to nearest whole dollar amount.) Ending inventory Cost of goods sold $ $ 44,380 108,220