National debt is the federal government’s total indebtedness at a moment in time.

Barter requires:

a. that the exchanged goods be portable. b. that the exchanged goods be durable. c. a coincidence of wants. d. that the exchange medium be divisible. e. an effective middleman.

The fact that the United States exports Budweiser beer and imports Heineken beer can be explained by:

a. the differences in labor productivity in the U.S. and other countries. b. the differences in factor endowments in the U.S. and its trading partners. c. the world price of Budweiser beer is lower than Heineken beer. d. the fact that production of Budweiser beer in the U.S. is inadequate compared to its demand. e. the preference for foreign brands of beer by a part of the U.S. population.