6. KEY QUESTION If the firm described in question 5 could engage in perfect price discrimination, what would be the level of output? of profits? Draw a diagram showing the relevant demand, marginal-revenue, average-total-cost, and marginal-cost curves, and the equilibrium price and output for a nondiscriminating monopolist. Use the same diagram to show the equilibrium position of a monopolist that is able to practise perfect price discrimination. Compare equilibrium outputs, total revenues, economic profits, and consumer prices in the two cases. Comment on the economic desirability of price discrimination.