Suppose a monopolist producing Q units of output faces the demand curve P = 20 - Q.

Question:

Suppose a monopolist producing Q units of output faces the demand curve P = 20 - Q. Its total cost when producing Q units of output is TC = F + Q2, where F is a fixed cost. The marginal cost is MC = 2Q.
a) For what values of F can a profit-maximizing firm charging a uniform price earn at least zero economic profit?
b) For what values of F can a profit-maximizing firm engaging in perfect first-degree price discrimination earn at least zero economic profit?