下列燃烧产物中属于不完全燃烧产物的有( )。

下列燃烧产物中属于不完全燃烧产物的有( )。A.SO2 B.NH3 C.醇类 D.醛类 E.醚类

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如右图,BD=CD,AE:DE=1:2,延长BE交AC于F,且AF=5cm.则AC的长为(  ).

如右图,BD=CD,AE:DE=1:2,延长BE交AC于F,且AF=5cm.则AC的长为(  ).A.30cm B.25cm C.15cm D.10cm

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设a>0,b>0,e是自然对数的底数(  ).

设a>0,b>0,e是自然对数的底数(  ).

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What year is the woman going to be in?

What year is the woman going to be in?A.The junior year. B.The freshman year. C.

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What is probably the man's position?

What is probably the man's position?A.Dean of Students. B.Lecturer in Speech Com

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