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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 perpetual inventory system. Also, on December 15 , Monson sells 15 units for $39 each. Purchases on December 710 units @ $25.00cost Purchases on December 1420 units a $31.00 cost Purchases on December 2115 units @ $33.00 cost etermine the costs assigned to ending inventory when costs are assigned based on the LIFO method