There are three consumer types, with inverse demands P=20-Q; P=20-1.5Q, P=20-2Q, respectively. There are 100 customers of each type. Your MC-8, there are no fixed costs. You are unable to differentiate between consumer types, but you would like to set multi-part tariffs in such a way that consumers will self-select into them. Derive the three pricing options you will set and the expected profit.