申論題

3. Company R and company E are two airlines both fly between London and Malaysia. Their demand curves are given by Q_E = 500 - 2P_E + P_R and Q_R = 500 - 2P_R + P_E.
 Q_E and Q_R stand for the number of passengers per day for company E and company R, respectively. The marginal cost of each carrier is $10 per passenger.

a) (6分) If company R sets a price of $100, what is the equation of company R’s demand curve and marginal revenue curve? What is company R’s profit-maximizing price when company E sets a price of $100?