问题
单项选择题
应用紫外线消毒空气时，有效距离与时间是
A．2.5m，不少于30min
B．3m，不少于30min
C．3.5m，不少于45min
D．2m，不少于30min
E．3m，不少于45min
答案
参考答案：D
解析：紫外线灯管消毒室内空气时，有效照射距离不应超过2m，照射时间不应少于 30～60min。
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应用紫外线消毒空气时，有效距离与时间是
A．2.5m，不少于30min
B．3m，不少于30min
C．3.5m，不少于45min
D．2m，不少于30min
E．3m，不少于45min
参考答案：D
解析：紫外线灯管消毒室内空气时，有效照射距离不应超过2m，照射时间不应少于 30～60min。
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| It's a Sunday morning. Jack and his father 1 on a big bus. There are 2 people on it.Some of 3 come from America and some 4 England and Canada. They are all friends.They are going to the Summer Palace (颐和园).There are two 5 0n the bus. One is a man. He is the driver. He 6 the bus. 7 _ is a young woman. She 8 good English. She is talking about the Summer Palace. All the passengers(乘客) are listening 9 her. They like the Summer Palace. They want 10 it very much. | |||
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