You are the manager of a monopoly. A typical consumers inverse demand function for your firms product

Question:

You are the manager of a monopoly. A typical consumer’s inverse demand function for your firm’s product is P = 100 –20Q, and your cost function is C(Q) = 20Q.
a. Determine the optimal two-part pricing strategy.
b. How much additional profit do you earn using a two-part pricing strategy compared with charging this consumer a per-unit price?