Profit Suppose that a manufacturer produces two brands of a product, brand 1 and brand 2. Suppose the demand for brand 1 is x = 70 - p1 thousand units and the demand for brand 2 is y = 80 - p2 thousand units, where p1 and p2 are prices in dollars. If the joint cost function is C = xy, in thousands of dollars, how many of each brand should be produced to maximize profit? What is the maximum profit?