How does a monopoly maximizes its profits. What is price discrimination in context of monopolies?

Microeconomics.

Using supply and demand curves explain where appropriate :

a) How does a monopoly maximizes its profits 15%
b) What is price discrimination in context of monopolies? 5%
c) Inwhatsituationscanamonopolybejustified?5%
d) What can government do when faced with monopoly structures in key industries. Use
real life examples to support your answer. 5%