行为发生不但与价值和实现的可能性有关，而且与实现的时间有关，说的是行为的
A. 强化模式
B. 时间价值期望模式
C. 健康意识模式
D. 个人控制力模式
With which of the Ten Principles of Economics is the study of international trade most closely connected? ( )
A. People face tradeoffs.
B. Trade can make everyone better off.
C. Governments can sometimes improve market outcomes.
D. Prices rise when the government prints too much money.
What is the fundamental basis for trade among nations? ( )
A. shortages or surpluses in nations that do not trade
B. misguided economic policies
C. absolute advantage
D. comparative advantage
price ceiling is ( )
A. often imposed on markets in which “cutthroat competition” would prevail without a price ceiling.
B. a legal maximum on the price at which a good can be sold.
C. often imposed when sellers of a good are successful in their attempts to convince the government that the market outcome is unfair without a price ceiling.
D. All of the above are correct.
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