Great Falls Brewery's regular selling price for a case of beer is $15. Variable costs are $8 per case and fixed costs total $2 per case based on production of 250,000 cases. The fixed costs remain unchanged within a relevant range of 50,000 to 300,000 cases. After sales of 180,000 cases were projected for the year, a special order was received for an additional 30,000 cases. Required Calculate Great Falls Brewery's minimum acceptable selling price per case for the special order of 30,000 cases