Required information Trey Monson starts a merchandising business on December 1 and enters into the following three inventory purchases. Also, on December 15, Monson sells 30 units for $50 each. Purchases on December 7 Purchases on December 14 Purchases on December 21 20 units @ $20.00 cost 34 units @ $30.00 cost 30 units @ $36.00 cost Required: Monson sells 30 units for $50 each on December 15. Monson uses a perpetual inventory system. Determine the costs assigned to ending inventory when costs are assigned based on the weighted average method (Round your per unit costs to 2 decimal places.) Weighted Average. Perpetual Goods purchased of Cost per Inventory Date unit Value Cost of Goods Sold # of Cost per Cost of sold unit Goods Sold Inventory Balance Inventory of units unit Balance Cost per December 7 $ 0.00 December 14 $ 0.00 Average cost $ 0.00 December 15 $ 0.00 December 21 $ 0.00 0 Average cost Totals $ 0.00