Questions 1~9 are multiple-choice questions. Choose the best possible answer out of the choices from the list.(1~2題每題2分・3~9題每題3分)
Questions 1~9 United Parcel Service (UPS) and FedEx Corporation (FedEx) are two leading delivery services companies andmain competitors to each other. When UPS and FedEx set their pricing strategy, their decisions are based on strategicconsiderations regarding the behavior of its competitors, such as pricing, output, advertising, investment, etc., and the situation canbe highly complicated. A number of researchers have developed analytical models of optimal pricing to understand and explain thefirms' behavior. Suppose there are only two firms, UPS and FedEx, in the industry. The two firms produce a homogeneous good (delivery), andthey compete by setting prices simultaneously and consumers want to buy everything from a firm with a lower price. Supposeeach of the two firms has fixed costs of $20 and zero variable costs. They face the same demand curves: UPS's demand QU = 12 -2PU + PF
 FedEx's demand QF = 12 - 2PF + PU
 Where Pu refers to UPS's price and Pp refers to FedEx's price.
 
【題組】1. In Nash equilibrium, what is the price UPS will charge?
(A) $2
(B) $4
(C) $6
(D) $8