Which of the following is not an explanation for structural unemployment?

Under a managed float, if U.S. demand for British goods drops, which of the following actions would the Bank of England need to take in order to stop any movement in the dollar-pound exchange rate?

a. Buy British pounds for dollars in order to shift the demand curve for pounds leftward b. Sell British pounds for dollars in order to shift the supply curve for pounds leftward c. Sell British pounds for dollars in order to shift the supply curve for pounds rightward d. Buy British pounds for dollars in order to shift the demand curve for pounds rightward e. Do nothing, since purchasing power parity will correct the situation in the short run.

Under a managed float,

a. a central bank allows the forces of supply and demand to determine the exchange rate b. a nation can have neither a trade deficit nor a trade surplus c. a nation "pegs" its price level to a foreign currency d. a nation "pegs" its price level at some fixed value e. a central bank intervenes in the foreign exchange market to stabilize its exchange rate