寡占市場的問題...(急) - 經濟

下下禮拜要參加研究所考試了，這邊有一個問題困擾我
懇請各位能幫幫我。。。

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Two firms compete by choosing price. their demand functions are

Q1=20-P1+P2 and Q2=20+P1-P2



where P1 and P2 are the price charged by each firm respectively and
Q1 and Q2 are the resulting demands. Note that the demand for each good
depends only on the difference in price; if the two firms
colluded and set the same price, they could make that price as
high as they want, and earn infinite profits. Marginal costs are zero.




1. Suppose the two firms set their prices at the same time. Find the
resulting Nash equilibrium. What price will each firm charge,
how much will it sell, and what will its profit be?



2. Suppose Firm 1 sets its price first and then Firm 2 sets its price.
What price will each firm charge, how much will it sell,
and what will its profit be?



這是在講秦柏霖勾結是嗎??? 怎麼算啊????







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