药物与毒物之间没有绝对的界限，在一定条件下可以相互转化。
A. 对
B. 错
药物对机体的作用属于药物代谢动力学研究的内容
A. 对
B. 错
What are the two new forms of music developed by the musicians in the southern United States?
A. Jazz
B. The blues
Country music
D. R&B
The text is mainly about _____.
A. the life of Elvis Presley
B. the history of American music
C. the development of rock and roll
D. black Africans and white European music
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