You win $100 in a basketball pool. You have a choice between spending the money now and putting it away for a year in a bank account that pays 10 percent interest. The opportunity cost of spending the $100 now is ( )
A. to spend $100 one year from now
B. to spend $105 one year from now
C. to spend $115 one year from now
D. to spend $95 one year from now.
查看答案
A point inside the production possibilities frontier is ( )
A. efficient, but not feasible.
B. feasible, but not efficient.
C. both efficient and feasible.
D. neither efficient nor feasible.
All of the following topics fall within the study of microeconomics EXCEPT ( )
A. the impact of cigarette taxes on the smoking behavior of teenagers.
B. the role of Microsoft’s market power in the pricing of software.
C. the effectiveness of antipoverty programs in reducing homelessness.
D. the influence of the government budget deficit on economic growth.
当空气漏入凝汽器后,凝汽器内的真空______ 、换热效果______ 。(填:升高、降低、保持不变)
凝汽式汽轮机中间级,流量变化时,级的理想比焓降______ 。(填:增大、减小、不变)
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