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Cast Iron Grills, Inc., manufactures premium gas barbecue grills. The company uses a periodic inventory system and the LIFO cost method for its grill inventory. Cast Iron's December 31, 2016, fiscal year-end inventory consisted of the following (listed in chronological order of acquisition) Units Unit Cost 7,400 $ 900 5,200 8,400 100 1,000 The replacement cost of the grills throughout 2017 was $1,200. Cast Iron sold 39,000 grills during 2017 The company's selling price is set at 200% of the current replacement cost