Tom is a castaway who washes up on a remote island. He can kill eight birds per hour or catch ten fish per day. The natives on the island can kill ten birds per day or catch twenty fish per day. The natives have a comparative advantage in:
a. hunting birds

The above figure shows the U.S. market for replacement cell phone batteries. With free international trade, the United States

A) exports 300,000 batteries. B) imports 500,000 batteries. C) imports 400,000 batteries. D) exports 700,000 batteries. E) imports 800,000 batteries.

Market failures are less likely to occur whenever

A) private returns are greater than social returns. B) social returns are greater than private returns. C) the free market produces less than what is socially optimal. D) new firms can easily attract start-up capital.