No sale units listed but it does say " at december 31st, Synergy counts seven units of inventory on hand"

The periodic Inventory records of Synergy Prosthetics indicate the following for the month of December (Click the icon to view the inventory records.) At December 31, Synergy counts seven units of inventory on hand. Compute ending merchandise inventory and cost of goods sold for Synergy using the weighted-average inventory costing method. Weighted-average Ending Merchandise Inventory Cost of Goods Sold 0 Data Table Dec. 1 Beginning merchandise inventory 8 Purchase 10 units 12 units 15 units 10 units @ $ 40 each @ $ 45 each @ $ 45 each @ $50 each 15 Purchase 26 Purchase Enter any number in the edit fields and then cod Print Done