The amount by which the expected return on a risky asset exceeds the return on an otherwise comparable safe asset is known as the

Consider a large public university in which a chemistry lecture is usually attended by 300 students or so but with large amounts of available seats on any given day

Is this a pure public good? If not, why not? Is this good likely to be provided in an efficient manner if the professor is vigilant in making sure that only registered students attend? Explain.

When an economy is in a liquidity trap

A) monetary policy cannot be used to influence the exchange rate. B) monetary policy can be used to drive interest rates down, but not to drive them up. C) there is an excess demand for bonds. D) people and institutions avoid holding cash balances. E) it can escape only by introducing a hard, or illiquid, currency.