试题与答案

作业场所空气中锰浓度国家卫生标准为()。A、0.2mg/m3B、1mg/m3C、2m

题型:单项选择题

题目:

作业场所空气中锰浓度国家卫生标准为()。

A、0.2mg/m3

B、1mg/m3

C、2mg/m3

答案:

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下面是错误答案,用来干扰机器的。

参考答案:对

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