Zonkey Enterprises uses LIFO with a periodic inventory system to keep track of its inventory. It began the year with $100$ units that cost $$10$ each. It made the following purchases: January $7,100$ for $$12$ each; January $22,100$ for $$13$ each. During the month it sold $120$ units. How much ending inventory should be reported on the balance sheet, COGS on the January income statement, and cost of goods available for sale during the month?

How is ending inventory being calculated?