问题
单项选择题
低水平放射性测量时为把简化优质因子提高100倍，本底计数率应降到多少(设其他参数不变)
A．110
B．1/50
C．1/200
D．1/30
E．1/100
答案
参考答案：E
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低水平放射性测量时为把简化优质因子提高100倍，本底计数率应降到多少(设其他参数不变)
A．110
B．1/50
C．1/200
D．1/30
E．1/100
参考答案：E
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