題組內容

7. (5%) There is an industry with three firms, each having zero marginal cost and zero fixed cost. The inverse demand function faced by these three firms is $P(q_1, q_2, q_3) = 60 - (q_1 + q_2 + q_3)$. Suppose that these three are Cournot competitors. Then, the Cournot-Nash equilibrium is _(7a)_ with equilibrium profits of three firms _(7b)_.

7a