根据科斯定理,一般来说,不管是由污染者还是受污染者负担降低污染的成本空气污染的数率最优水平是固定不变的。
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Who are described in the recording?[音频]
A woman and a man in London.
B. Two young people in Tokyo.
C. Some American teenagers in New York City.
D. All of the above.
How many fashion styles are mentioned?[音频]
A. 1
B. 2
C. 3
D. 4
Findthecorrect phrase fromthesecondcollumtofillintheblanksinthesentencesinthefirstcollum.
走姿的基本规范包括①头正 ②肩平 ③背直 ④步履匀称
A. ①②
B. ②③
C. ①②③
D. ①②③④
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