Suppose you're willing to tutor a student for $10 an hour. The student pays you $15 an hour. What is your producer surplus?

Assume a simplified banking system subject to a 10 percent required reserve ratio. If there is an initial increase in excess reserves of $90,000 and all possible loans are made, the money supply:

a. increases $90,000. b. increases $900,000. c. increases $990,000. d. decreases $90,000.

Suppose that two firms are producers of spring water, which can be obtained at zero cost. The market demand curve for their combined output is p = 100 - Q where p is the price and Q is the amount of spring water sold by both together. If the two producers act in accord with the Cournot model, their combined output will be

A. 66.66. B. 0. C. 50. D. 33.33.