支气管肺炎有缺氧表现,鼻导管给氧的流量为
A.0.2~0.5L/min
B.0.5~lL/min
C.1~2L/min
D.2~3L/min
E.2~4L/rain
参考答案:B
Many tall buildings _______ in Shengsi in the past few years.
A.has been built
B.have been built
C.were built
D.have built
煤的低温干馏所产的煤气,主要组分为甲烷、氢气、一氧化碳及一()一等物质。
A.杂质
B.重碳氢化合物
C.二氧化碳