A signaling theory of education suggests that educational attainment:. a. is a signal of high marginal productivity. b. is correlated with natural ability. c. increases the productivity of low-ability workers. d. both a and b are correct.

2. which of the following statements about interest is true? a. interest is a one-time fee that you pay for lending money. b. interest is expressed as a percentage of the amount you are borrowing. c. because interest rates tend to be small numbers, they typically don't have much effect on the price of the goods you're purchasing. d. interest is a penalty that you pay when you don't pay your bills on time.