Division A of a company is currently operating at 50% capacity. It produces a single product and sells all its production to outside customers for $13 per unit. Variable costs are $7 per unit, and fixed costs are $6 per unit at the current production level. Division B, which currently purchases this product from an outside supplier for $12 per unit, would like to purchase the product from Division A. Division A will operate at 80% capacity to meet outside customers’ and Division B’s demand. What is the minimum price that Division A should charge Division B for this product?