如图,正方形的边长为2cm,剪去四个角后成为一个正八边形,则这个正八边形的边长等于 ( )cm.
2﹣
有氯气和氧气的混合气体125 mL,将点燃的氢气放入混合气体中,待混合气体完全反应后,测得消耗氢气200 mL(气体体积均在相同条件下测定)。则原混合气体中氯气和氧气的体积比是( )
A.2∶3
B.3∶2
C.3∶5
D.5∶4
— _____?
— She's tall and slim. [ ]
A. What's she like
B. What does she like
C. How does she look like
D. How is she like