Athmer Corporation sells a product for $18 per unit, and the standard cost card for the product shows the following costs: Direct material $ 1 Direct labor 2 Overhead (80% fixed) 7 Total $10 Refer to Athmer Corporation. Assume that Athmer has sufficient idle capacity to produce the 1,000 units. If Athmer wants to increase its operating profit by $5,600, what would it charge as a per-unit selling price?