5mol CO2中含有6.02×1023 个氧原子和6g碳原子。
参考答案:对
M: Morning, Lily. What kept you
W: Morning, Stan. Sorry I’m so late, but you know, it’s impossible to find a parking place round here.
Why was the woman late ()
A. There was something wrong with her car.
B. She got up too late.
C. There was no parking place nearby.
D. She got lost on her way to Andrew’s home.
婴儿自我意识发展的两个关键阶段是( )。
A.出生后的第一年
B.1~2岁
C.1~1.5岁
D.2~3岁