湿式自动喷水灭火系统通常适用于室内温度不低于()且不高于70℃的环境。
A.4℃
B.5℃
C.6℃
D.7℃
参考答案:A
用所给单词的适当形式填空.
1. We should give up those _______ (waste) habits in order to save our world.
2. The foreigners had an _______ (enjoy) time on the Great Wall yesterday.
3. I think __________(environment) education for kids is necessary.
4. Most students in our school often collect _______ (reuse) waste for recycling.
5. If we don't look after our earth well, the future will be _______ (hope).
在220kV线路带电情况下,砍剪靠近线路的树木时,人员、树木、绳索应与导线保持()m的安全距离。
A.5.0
B.4.0
C.3.0
D.2.5