曼昆經(jīng)濟學原理第六版答案（微觀部分）英文

1、1SOLUTIONS SOLUTIONS SOLUTIONS SOLUTIONS TO TO TO TO TEXT TEXT TEXT TEXT PROBLEMS: PROBLEMS: PROBLEMS: PROBLEMS:Quick Quick Quick Quick Quizzes Quizzes Quizzes Quizzes1. The four principles of economic decisionmaking are

2、: (1) people face tradeoffs; (2) the cost ofsomething is what you give up to get it; (3) rational people think at the margin; and (4) people respond to incentives. People face tradeoffs because to get one thing that they

3、 like, they usuallyhave to give up another thing that they like. The cost of something is what you give up to get it,not just in terms of monetary costs but all opportunity costs. Rational people think at the margin by t

4、aking an action if and only if the marginal benefits exceed the marginal costs. People respond toincentives because as they compare benefits to costs, a change in incentives may cause their behavior to change.2. The thre

5、e principles concerning economic interactions are: (1) trade can make everyone betteroff; (2) markets are usually a good way to organize economic activity; and (3) governments can sometimes improve market outcomes. Trade

6、 can make everyone better off because it allowscountries to specialize in what they do best and to enjoy a wider variety of goods and services. Markets are usually a good way to organize economic activity because the inv

7、isible hand leads markets to desirable outcomes. Governments can sometimes improve market outcomes becausesometimes markets fail to allocate resources efficiently because of an externality or market power.3. The three pr

8、inciples that describe how the economy as a whole works are: (1) a country’sstandard of living depends on its ability to produce goods and services; (2) prices rise when the government prints too much money; and (3) soci

9、ety faces a short-run tradeoff between inflation and unemployment. A country’s standard of living depends on its ability to produce goods andservices, which in turn depends on its productivity, which is a function of the

10、 education of workers and the access workers have to the necessary tools and technology. Prices rise when thegovernment prints too much money because more money in circulation reduces the value of money, causing inflatio

11、n. Society faces a short-run tradeoff between inflation and unemployment that isonly temporary and policymakers have some ability to exploit this relationship using various policy instruments.Questions Questions Question

12、s Questions for for for for Review Review Review Review1. Examples of tradeoffs include time tradeoffs (such as studying one subject over another, or studying at all compared to engaging in social activities) and spendin

13、g tradeoffs (such as whether to use your last ten dollars on pizza or on a study guide for that tough economics course).2. The opportunity cost of seeing a movie includes the monetary cost of admission plus the time cost

14、 of going to the theater and attending the show. The time cost depends on what else you might dowith that time; if it's staying home and watching TV, the time cost may be small, but if it's working an extra three

15、 hours at your job, the time cost is the money you could have earned.3. The marginal benefit of a glass of water depends on your circumstances. If you've just run amarathon, or you've been walking in the desert s

16、un for three hours, the marginal benefit is very high. But if you've been drinking a lot of liquids recently, the marginal benefit is quite low. Thepoint is that even the necessities of life, like water, don't al

17、ways have large marginal benefits.4. Policymakers need to think about incentives so they can understand how people will respond to the policies they put in place. The text's example of seat belts shows that policy ac

18、tions can havequite unintended consequences. If incentives matter a lot, they may lead to a very different typeChapter 1/Ten Principles of Economics F 3the benefits. One is to compare the vacation with what you would do

19、in its place. If you didn'tgo on vacation, would you buy something like a new set of golf clubs? Then you can decide ifyou'd rather have the new clubs or the vacation. A second way is to think about how much work

20、you had to do to earn the money to pay for the vacation; then you can decide if the psychological benefits of the vacation were worth the psychological cost of working.3. If you are thinking of going skiing instead of wo

21、rking at your part-time job, the cost of skiing includes its monetary and time costs, which includes the opportunity cost of the wages you are giving up by not working. If the choice is between skiing and going to the li

22、brary to study, thenthe cost of skiing is its monetary and time costs including the cost to you of getting a lower grade in your course.4. If you spend $100 now instead of saving it for a year and earning 5 percent inter

23、est, you are giving up the opportunity to spend $105 a year from now. The idea that money has a time value is thebasis for the field of finance, the subfield of economics that has to do with prices of financial instrumen

24、ts like stocks and bonds.5. The fact that you've already sunk $5 million isn't relevant to your decision anymore, since that money is gone. What matters now is the chance to earn profits at the margin. If you spe

25、ndanother $1 million and can generate sales of $3 million, you'll earn $2 million in marginal profit, so you should do so. You are right to think that the project has lost a total of $3 million ($6 million incosts an

26、d only $3 million in revenue) and you shouldn't have started it. That's true, but if youdon't spend the additional $1 million, you won't have any sales and your losses will be $5 million. So what matters

27、is not the total profit, but the profit you can earn at the margin. In fact, you'dpay up to $3 million to complete development; any more than that, and you won't be increasing profit at the margin.6. Harry sugges

28、ts looking at whether productivity would rise or fall. Productivity is certainlyimportant, since the more productive workers are, the lower the cost per gallon of potion. Ronwants to look at average cost. But both Harry

29、and Ron are missing the other side of theequation?revenue. A firm wants to maximize its profits, so it needs to examine both costs andrevenues. Thus, Hermione is right?it’s best to examine whether the extra revenue would

30、 exceedthe extra costs. Hermione is the only one who is thinking at the margin.7. a. The provision of Social Security benefits lowers an individual’s incentive to save for retirement. The benefits provide some level of i

31、ncome to the individual when he or sheretires. This means that the individual is not entirely dependent on savings to supportconsumption through the years in retirement.b. Since a person gets fewer after-tax Social Secur

32、ity benefits the greater is his or her earnings, there is an incentive not to work (or not work as much) after age 65. The moreyou work, the lower your after-tax Social Security benefits will be. Thus the taxation ofSoci

33、al Security benefits discourages work effort after age 65.8. a. When welfare recipients who are able to work have their benefits cut off after two years, they have greater incentive to find jobs than if their benefits we

34、re to last forever.b. The loss of benefits means that someone who can't find a job will get no income at all, so the distribution of income will become less equal. But the economy will be more efficient,since welfare

35、 recipients have a greater incentive to find jobs. Thus the change in the lawis one that increases efficiency but reduces equity.9. By specializing in each task, you and your roommate can finish the chores more quickly.