10. A single-price monopolist faces the following demand and marginal revenue curves for his product: 120 - Q , MR=120-2Q; And Total Cost of production and marginal cost may be expressed by: TC = 1/2 Q2 + 40 , MC= Q.

a) Find his profit-maximizing output and price of this monopoly.

b) If this monopolist is now able to identify customer needs and charge a different price for each and every customer, what is the profit maximizing output