Consider a Bertrand oligopoly consisting of four firms

Consider a Bertrand oligopoly consisting of four firms that produce an identical product at a marginal cost of $260. The inverse market demand for this product is P = 500 -3Q.

TR = PQ = 500Q-3Q²

MR = dTR/dQ= 500-6Q

At equilibrium,

MR = MC

500-6Q = 260

=> Q = 40

P = 500-3*40 = 380

a. Determine the equilibrium level of output in the market:
b. Determine the equilibrium market price:
c. Determine the profits of each firm: