The marginal cost curve passes through the minimum point of the average fixed cost curve.

此题为判断题(对，错)。

At the quantities where the marginal cost curve intersects the average variable cost (AVC) curve and the average total cost (ATC) curve, respectively:

A.AVC and ATC are at their minimum points

B.AVC is at its minimum point and ATC is increasing

C.ATC is at its minimum point and AVC is decreasing

Suppose the cost of operating a 75 room hotel for a night is $6,000 and there are 5 empty rooms for tonight. If the marginal cost of operating one room for one night is $40, the hotel manager should rent one of the empty rooms only if a customer is willing to pay

A．more than ＄40, as the average benefit will exceed the marginal cost．

B．more than ＄40, as the marginal benefit will exceed the marginal cost．

C．more than ＄80, as the average benefit will exceed the marginal cost．

D．more than ＄80, as the marginal benefit will exceed the marginal cost．

Karen Rusa was a 30-year-old woman and the mother of four children. For the past several months Karen had been experiencing repetitive thoughts that centered around her children' s safety. She frequently found herself imagining that a serious accident had occurred; she was unable to put these thoughts out of her mind. On one such occasion she imagined that her son, Alan, had broken his leg playing football at school. There was no reason to believe that an accident had occurred, but she kept thinking about the possibility until she finally called the school to see if Alan was all right. Even after receiving their assurance that he had not been hurt, she described herself as being somewhat surprised when he later arrived home unharmed. Karen also noted that her daily routine was seriously hampered by an extensive series of counting work that she performed throughout each day. Specific numbers had come to have a special meaning to her; she found that her preoccupation with these numbers was hampering her ability to perform. everyday activities. One example was grocery shopping. Karen believed that if she selected the first item on the shelf, something terrible would happen to her oldest child. If she selected the second item, some unknown disaster would fall on her second child, and so on for the four children. Karen' s preoccupation with numbers extended to other activities, most notable the pattern in which she smoked cigarettes and drank coffee. If she had one cigarette; she believed that she had to smoke at least four in a row, or one of her children would be harmed in some way. If she drank one cup of coffee, she felt compelled to drink four. Karen acknowledged the unreasonableness of these rules, but, nevertheless, maintained that she felt more comfortable. When she observed them earnestly, when she was occasionally in too great a hurry to observe these rules, she experienced considerable anxiety, in the form. of a subjective feeling of dread and fear. She described herself as tense, uneasy, and unable to relax during these periods. The occurrence of rarely minor accidents does not reduce her belief that she had been directly responsible because of her inability to observe the rules about number.

The main idea of this passage is to

A．describe a woman who suffered from a psychological disease.

B．warn the readers against any imagination.

C．explain the reason why Karen had such fanciful thoughts.

D．present a case for the readers to study.

Karen Rusa was a 30-year-old woman and the mother of four children. For the past several months Karen had been experiencing repetitive thoughts that centered around her children's safety. She frequently found herself imagining that a serious accident had occurred; she was unable to put these thoughts out of her mind. On one such occasion she imagined that her son, Alan, had broken his leg playing football at school. There was no reason to believe that an accident had occurred, but she kept thinking about the possibility until she finally called the school to see if Alan was all right. Even after receiving their assurance that he had not been hurt, she described herself as being somewhat surprised when he later arrived home unharmed. Karen also noted that her daily routine was seriously hampered by an extensive series of counting work that she performed throughout each day. Specific numbers had come to have a special meaning to her; she found that her preoccupation with these numbers was hampering her ability to perform. everyday activities. One example was grocery shopping. Karen believed that if she selected the first item on the shelf, something terrible would happen to her oldest child. If she selected the second item, some unknown disaster would fall on her second child, and so on for the four children. Karen's preoccupation with numbers extended to other activities, most notable the pattern in which she smoked cigarettes and drank coffee. If she had one cigarette; she believed that she had to smoke at least tour in a row, or one of her children would be harmed in some way. If she drank one cup of coffee, she felt compelled to drink tour. Karen acknowledged the unreasonableness of these rules, but, nevertheless, maintained that she felt more comfortable. When she observed them earnestly, when she was occasionally in too great a hurry to observe these rules, she experienced considerable anxiety, in the form. of a subjective feeling of dread and fear. She described herself as tense, uneasy, and unable to relax during these periods. The occurrence of rarely minor accidents does not reduce her belief that she had been directly responsible because of her inability to observe the rules about number.

The main idea of this passage is to

A．describe a woman who suffered from a psychological disease.

B．warn the readers against any imagination.

C．explain the reason why Karen had such fanciful thoughts.

D．present a case for the readers to study.

Karen Rusa was a 30-year-old woman and the mother of four children. For the past several months Karen had been experiencing repetitive thoughts that centered around her children's safety. She frequently found herself imagining that a serious accident had occurred; she was unable to put these thoughts out of her mind. On one such occasion she imagined that her son, Alan, had broken his leg playing football at school. There was no reason to believe that an accident had occurred, but she kept thinking about the possibility until she finally called the school to see if Alan was all right. Even after receiving their assurance that he had not been hurt, she described herself as being somewhat surprised when he later arrived home unharmed. Karen also noted that her daily routine was seriously hampered by an extensive series of counting work that she performed throughout each day. Specific numbers had come to have a special meaning to her; she found that her preoccupation with these numbers was hampering her ability to perform. everyday activities. One example was grocery shopping. Karen believed that if she selected the first item on the shelf, something terrible would happen to her oldest child. If she selected the second item, some unknown disaster would fall on her second child, and so on for the four children. Karen's preoccupation with numbers extended to other activities, most notable the pattern in which she smoked cigarettes and drank coffee. If she had one cigarette; she believed that she had to smoke at least tour in a row, or one of her children would be harmed in some way. If she drank one cup of coffee, she felt compelled to drink tour. Karen acknowledged the unreasonableness of these rules, but, nevertheless, maintained that she felt more comfortable. When she observed them earnestly, when she was occasionally in too great a hurry to observe these rules, she experienced considerable anxiety, in the form. of a subjective feeling of dread and fear. She described herself as tense, uneasy, and unable to relax during these periods. The occurrence of rarely minor accidents does not reduce her belief that she had been directly responsible because of her inability to observe the rules about number.

The main idea of this passage is to

A．describe a woman who suffered from a psychological disease.

B．warn the readers against any imagination.

C．explain the reason why Karen had such fanciful thoughts.

D．present a case for the readers to study.

For the past several decades, it seems there's been a general consensus on how to get ahead in America: Get a college education, find a reliable job, and buy your own home. But do Americans still believe in that path, and if they do, is it attainable? The most recent National Journal poll asked respondents about the American dream, what it takes to achieve their goals, and whether or not they felt a significant amount of control over their ability to be successful. Overwhelmingly, the results show that today， the idea of the American dream—and what it takes to achieve it—looks quite different than it did in the late 20th century. By and large, people felt that their actions and hard work—not outside forces—were the deciding factor in how their lives turned out. But respondents had decidedly mixed feelings about what actions make for a better life in the current economy. In the last seven years, Americans have grown more pessimistic about the power of education to lead to success. Even though they see going to college as a fairly achievable goal, a majority—52 percent—think that young people do not need a four-year college education in order to be successful. Miguel Maeda, 42, who has a master's degree and works in public health, was the first in his family to go to college, which has allowed him to achieve a sense of financial stability his parents and grandparents never did. While some, like Maeda, emphasized the value of the degree rather than the education itself, others still see college as a way to gain new perspectives and life experiences. Sixty-year-old Will Fendley, who had a successful career in the military and never earned a college degree, thinks "personal drive" is far more important than just going to college. To Fendley， a sense of drive and purpose, as well as an effective high-school education, and basic life skills, like balancing a checkbook, are the necessary ingredients for a successful life in America. 51.It used to be commonly acknowledged that to succeed in America, one had to have _____.

A.an advanced academic degree

B.an ambition to get ahead

C.a firm belief in their dream

D.a sense of drive and purpose

52.What is the finding of the latest National Journal poll concerning the American dream_____

A.More and more Americans are finding it hard to realize.

B.It remains alive among the majority of American people.

C.Americans' idea of it has changed over the past few decades.

D.An increasing number of young Americans are abandoning it.

53.What do Americans now think of the role of college education in achieving success_____

A.It still remains open to debate.

B.It has proved to be beyond doubt.

C.It is no longer as important as it used to be.

D.It is much better understood now than ever.

54.How do some people view college education these days_____

 A.It promotes gender equality.

B.It needs to be strengthened.

C.It adds to cultural diversity.

D.It helps broaden their minds.

55.What is one factor essential to success in America, according to Will Fendley_____

A.A desire to learn and to adapt.

B.A strong sense of responsibility.

C.A willingness to commit oneself.

D.A clear aim and high motivation.