7. If a cocoa shipping firm sells Q tons of cocoa in the UK, the price received is given by PE-al-1Q 0n the other hand, if it buys Q tons from its only source in Ghana, the price it has to pay is given by Pc -a Q. In addition, it costs y per ton to ship cocoa from its supplier in Ghana to its customers in the UK (its only market). The numbers ar, a2, and y are all positive. a. Express the cocoa shipper’s profit as a function of Q, the number of tons shipped. b. Assuming that a – a2 y 0, find the profit-maximizing shipment of cocoa.