对深度超过( )m,可能存在危险性气体的挖掘现场,应进行气体检测。
A.1.2
B.1.5
C.1.8
参考答案:A
下列实验方法正确的是
A.用带火星的木条区别氢气和氮气
B.用肥皂区别硬水和软水
C.用灼烧的方法区别黄铜(铜锌合金)和黄金
D.用滴加澄清石灰水,震荡的方法区别二氧化碳和一氧化碳
— Did you get any fish when you were fishing yesterday?
— Yes. I got than any of them. [ ]
A. many
B. many more
C. much more
D. the most