Three firms, A, B and C engage in Bertrand price competition in a market with inverse demand given by P = 10 - Q. Whenever a firm undercuts the rivals' price, it gets the entire demand. If firms charge the same lowest price in the market, they share the market. If a firm charges a price more than any rival, it has zero market share. Suppose there are no fixed costs and the marginal costs of the firms are: c(A) = 8, c(B) = 6 and c(C) = 4. a. Find a Nash equilibrium of this game. What are each firm's prices and profits? Explain your solution. b. Suppose firm B leaves the market. Draw each firm's best response on a diagram and find a Nash equilibrium of this duopoly game