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Use the following information to complete this exercise: sales, 650 units for $9, 600; beginning inventory, 400 units; purchases, 500 units; ending inventory, 250 units; and operating expenses, $4, 600. Complete the table for each situation. In Situations A and B (costs rising), assume the following: beginning inventory, 400 units at $6 = $2, 400; purchases, 500 units at $8 = $4,000. In Situations C and D (costs falling), assume the opposite; that is, beginning inventory, 400 units at $8 = $3, 200; purchases, 500 units at $6 = $3,000. Use periodic inventory procedures