The figure above shows the marginal benefit and marginal cost curves for pizza. In the figure, what is the efficient quantity of pizza?

Suppose the economy is operating below its full employment level. The Fed

A) can move the economy toward the full employment level by expanding the money supply to increase aggregate supply. B) can move the economy toward the full employment level by expanding the money supply to increase aggregate demand through both its direct and its indirect effects. C) can move the economy toward the full employment level by expanding the money supply to increase aggregate demand and to hold prices constant. D) is powerless to affect either aggregate demand or aggregate supply. Fiscal policy is needed.

In the context of portfolio diversification,

A) investors are compensated for diversifiable risk in the portfolio. B) prudent investors should hold about three to five stocks in their portfolio. C) a stock index mutual fund is a financial intermediary that offers small investors a way to participate in the performance of the stock market as a whole. D) financial intermediaries make it more difficult to be diversified.