How does the speaker feel when they stay in the out-of-doors in nature?
A. Feel peaceful.
B. Feel boring.
C. Feel excited.
D. Feel exhausted.
查看答案
What would happen to the speaker if staying in the city?
A. Becoming great
B. Feeling loved.
C. Being sad.
D. Having ultimate joy.
回转建模是指_____________________________________________________________________。
同样的商品对同样的人，其效用会因时间和地点的不同而不同。
A. 对
B. 错
只要商品的数量在增加，消费者得到的总效用就一定增加。
A. 对
B. 错
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