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Linden Company manufactures and sells a single product. Cost data for the product follow: During the last year, 30,000 units were produced and 25,000 units were sold. The Finished Goods inventory account at the end of the year shows a balance of $110,000 and 5,000 unsold units. What type of costing method is the company using? a. FIFO costing. b. Absorption costing. c. Average costing. d. Variable costing. e. None of the above