问题
单项选择题
氧气检测应设定缺氧报警和富氧报警两级检测报警值，缺氧报警值应设定为（）%。
A.19.5
B.20.9
C.23.5
答案
参考答案：A
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氧气检测应设定缺氧报警和富氧报警两级检测报警值，缺氧报警值应设定为（）%。
A.19.5
B.20.9
C.23.5
参考答案：A
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