问题
单项选择题
不透光烟度计是用于连续测量汽车排气的（）的仪器。
A．CO
B．HC
C．光吸收系数
答案
参考答案：C
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不透光烟度计是用于连续测量汽车排气的（）的仪器。
A．CO
B．HC
C．光吸收系数
参考答案：C
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