Required information [The following information applies to the questions displayed below.] Trey Monson starts a merchandising business on December 1 and enters into the following three inventory purchases. Monson uses a periodic inventory system. Also, on December 15 , Monson sells 27 units for $20 each. Determine the costs assigned to ending inventory when costs are assigned based on the FIFO method. Determine the costs assigned to ending inventory when costs are assigned based on the weighted average method. (Round cost per units to 2 decimal places.)