Shown below is activity for one of the products of Denver Office Equipment January 1 balance, 540 units $50 per unit $27,000 Purchases: January 10:540 units $55 per unit January 20: 1,020 units $56 per unit Sales: January 12: 910 units January 28 : 790 units Required: Compute the January 31 ending inventory and cost of goods sold for January, assuming Denver uses LIFO and a periodic inventory system