If a currency such as the US$ is traded in a competitive market, a(n) ________ in demand for the US$ ________ the price of the US$ in terms of another currency such as the Japanese Yen (¥)

Under a liquidity trap in the New Keynesian model,

A) prices cannot be sticky. B) monetary policy is ineffective. C) the economy is always efficient. D) fiscal policy is ineffective.

If there are external benefits for good X then which of the following would be true?

a. The socially efficient amount of good X can be achieved if society subsidizes consumers of good X. b. The socially efficient amount of good X does not exist. c. The socially efficient amount of good X can be achieved if society taxes consumers of good X. d. The socially efficient amount of good X will be equivalent to the free market equilibrium quantity.