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【多选题】
促进植物扦插生根的药剂有( )。A.
乙烯利
B.
萘乙酸
C.
吲哚丁酸
D.
赤霉素
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反馈参考答案：
举一反三
【单选题】传统的集合“并、交、差”运算施加于两个关系时，这两个关系应该满足的条件有（）。
A.
相对应的属性值不必须取自同一个域
B.
属性个数不相等
C.
对关系的属性及属性值没有要求
D.
属性个数相等
【简答题】传统集合的并、交、差运算施加于两个关系时,这两个关系的____必须相等。
【单选题】Mary _____ a photo of Professor Smith while he was making a speech.
A.
took
B.
takes
C.
would take
D.
has taken
【单选题】The professor ____ will be here tomorrow.
A.
is talked about
B.
talking about
C.
to be talked about
D.
being talked about
【简答题】Resident advisor/ TA/ Professor Giving you advice on how to _____________.
【单选题】Yates tries to lower Simpson down the mountain, but __________.
A.
he suddenly loses his strength
B.
he cannot communicate with Simpson
C.
Simpson hears nothing from Yates
D.
Simpson's injuries stop him from climbing up the rope or communicating with Yates
【简答题】传统的集合运算“并、交、差”运算施加于两个关系时,这两个关系必须 。
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