In a market characterized by externalities, the market equilibrium fails to maximize the total benefit to society as a whole

Why is the long-run aggregate supply curve a vertical line?

A) At that level of real GDP, the production costs are at their lowest level. B) At that level of real GDP, production costs have fully adjusted to price changes. C) At that level of real GDP, the unemployment rate is 0 percent. D) At that level of real GDP, the inflation rate is 0 percent.

An increase in the foreign price of the U.S. dollar is called:

a. depreciation of the U.S. dollar. b. appreciation of the U.S. dollar. c. appreciation of the foreign currency. d. readjustment of the U.S. dollar. e. readjustment of the foreign currency.