Estimate the equilibrium price, output, consumer surplus.

Consider a monopoly with a demand function D: P = 20 -Q

Let the cost function be C= 10+ Q + Q2

a) Compute the monopoly equilibrium.

b) Compute the consumer surplus.

c) Suppose this company practices two-parts tariffs,

I) Compute the optimal output.

II) Compute the size of the optimal "membership fee".

d) Suppose this company practices perfect price discrimination,

I) Compute the optimal output,

II) Compute the total amount of money the company will charge