The author implies that______.
Americans waste energy
B. Americans have to import a great quantity of gas each year
C. anti-pollution devices on automobiles are not effective
D. small cars use energy efficiently
国民收入中的边际消费倾向的值越大，则()。
A. 边际储蓄倾向的值越大
B. 乘数的值就越小
C. 总支出曲线就越平坦
D. 总支出曲线就越陡
In Para. 4, the words "his peers" refer to which of the following？
A. His parents.
B. His teachers.
C. His financial experts.
D. His friends.
All the aged the author saw lived______.
A. highly respected
B. with their families and relatives
C. with a sense of usefulness
D. all of the above
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