Trey Monson starts a merchandising business on December 1 and enters into three inventory purchases: Purchases on December 7 18 units @ $4.00 cost Purchases on December 14 35 units @ $6.00 cost Purchases on December 21 28 units @ $7.00 cost Required: Monson sells 28 units for $10 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.)