The first labor unions in the United States were

Over the course of the 20th century, _____

a. federal government expenditures have grown less than state and local expenditures b. federal government expenditures have increased substantially as a percentage of GDP c. federal government expenditures remained fairly constant except during wartime d. federal government expenditures have always been higher than the expenditures of state and local governments.

Oligopoly occurs when

a. a few firms sell many different products. b. a few firms sell to a few large buyers. c. many firms dominate a single market. d. a few firms dominate a single market.