9. Suppose UPS and FedEx plan to improve the on-time delivery rate for the peak period, and the expected payoff matrix for the
2020 holiday season is changed as the following table. Choose all of the Nash equilibrium of this game.
(1) Both UPS and FedEx charge $5
(2) Both UPS and FedEx charge $5.5
(3) UPS charges $5 and FedEx charges $5.5
(4) UPS charges $5.5 and FedEx charges $5
(5) Both UPS and FedEx play a mixed strategy, where each firm charges $5 with a probability of 2/3 and charges $5.5 with a
probability of 1/3
(A) Only (I)
(B) Only (2)
(C) (3) and (4)
(D) (3),(4)& (5)