Doctors cannot learn which persons face the most danger until permanent hearing damage
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《危险化学品重大危险源辨识》标准()了辨识重大危险源的依据和方法。
A. 规定
B. 规范
C. 提出
D. 提示
challenge means to invite sb. to compete or fight to prove who is better. ()
Prototype refers to the process by which people use language to classify the world around and inside them. ()
在实施成人胸外心脏按压时有哪些注意事项(指按压手法)？
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