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Exoplex Company has has the following divisions organized as profit centers, the Coastal Division, Central Division, and Metro Division. The revenues and expenses for the divisions are as follows: Coastal Division Metro Division Central Division Corporate Revenues 900,000 625,000 $ 820,000 Operating expenses 490,000 280,000 530,000 Customer support 230,000 Purchasing 250,000 Information on usage of the service departments is: Coastal Division Metro Division Central Division Total Customer support: number of customer calls 2,000 4,000 6,000 12,000 Purchasing: number of purchase orders 1,500 2,300 1,200 5.000 How much is the service department charge rate for purchasing? 5.02 per purchase order $50 per purchase order S18 per purchase order $25 per urchase order