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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 periodic inventory system. Also, on December 15 , Monson sells 26 units for $25 each. The units sold, 13 are from the December 7 purchase and 13 are from the December 14 purchase. Determine the costs assigned to ending inventory when costs are assigned based on specific identification