Which of the following will cause the money supply to decline?

When the U.S. real interest rate rises ________

A) U.S. dollar assets earn a higher return relative to foreign assets B) makes U.S. exports cheaper in foreign currencies C) imports will decrease D) all of the above E) none of the above

In a market with positive externalities,

A) the efficient level of production is less than what competition will obtain. B) the efficient level of production is equal to what competition will obtain. C) the efficient level of production is more than what competition will obtain. D) there cannot be an efficient level of production.