血中Hb含量低于多少时,即使重度缺氧,亦难发现发绀()
A.<50g/L
B.<60g/L
C.<70g/L
D.<80g/L
E.<90g/L
参考答案:B
It is really a pity that as many as 58 lives didn’t ______ the big high-rise fire that happened in Shanghai on 15th.November,2010.
A.perform
B.succeed
C.remove
D.survive
在搬运射孔器、设备前,要对所经路径和摆放场所的杂物及湿滑地面如何处理?