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Great Falls Brewery's regular selling price for a case of beer is $17. Variable costs are $10 per case, and fixed costs total $4 per case, based on production of 200,000 cases. The fixed costs remain unchanged within a relevant range of 40,000 to 340,000 cases. After sales of 150,000 cases were projected for the year, a special order was received for an additional 20,000 cases. Required: Calculate Great Falls Brewery's minimum acceptable selling price for the special order of 20,000 cases. An analysis requires that relevant costs be identified. The only costs that are relevant are those which will differ depending on whether the special order is accepted. Determine relevant variable costs