Suppose demand is given by Qxd = 50 ? 4Px + 6Py + Ax, where Px = $4, Py = $2, and Ax = $50. What is the quantity demanded of good x?

In the textbook model of endogenous growth, in equilibrium, output grows at the rate of

A) sA - d. B) n + d. C) K. D) A.

Suppose a monopoly sells to two identifiably different types of customers, A and B, who are unable to practice arbitrage. The inverse demand curve for group A is PA = 10 - QA, and the inverse demand curve for group B is PB = 18 - QB. The monopolist is able to produce the good for either type of customer at a constant marginal cost of 2, and the monopolist has no fixed costs. If the monopolist is

able to practice group price discrimination, the values of the elasticities of the two groups at the profit-maximizing prices are A) ?A = -1.25, and ?B = -1.5. B) ?A = -1.5, and ?B = -1.25. C) ?A = -0.67, and ?B = -0.8. D) ?A = -0.8, and ?B = -0.67.