Suppose a firm in a competitive market produces and sells 8 units of output and has a marginal revenue of $8 . What would be the firm's marginal revenue if it instead produced and sold 4 units of output?

If two goods are perfect substitutes, then the indifference curves for those two goods would be

A) upward sloping and concave to the origin. B) downward sloping and convex to the origin. C) downward sloping and straight. D) L-shaped.

If price support policy increases producer surplus more than reducing consumer surplus, then

A) the policy leads to a Pareto-superior allocation. B) the policy leads to an increase in social welfare. C) the policy improves the efficiency of society. D) None of above.