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【简答题】
等同学“探究声音的产生”的装置如图所示，将系在细线上的乒乓球靠近音叉． （1）当同学用敲击音叉的时候，既能听到音叉发出的声音，又能观察到______．通过实验现象得出的结论是______． （2）乒乓球在实验中起到什么作用？______．这种思维方法叫做______（等效法/控制变量法/转换法类比法）． （3）若实验过程中同学加大敲击音叉的变化： ①听到和看到的现象会有什么样的变化？______． ②根据实验现象的变化，你又可以总结出什么结论？______．
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举一反三
【单选题】His uncle is a worker and has been working in the factory for more than ten years. _____.
A.
So is his aunt
B.
So has his aunt
C.
So his aunt does
D.
So it is with his aunt
【单选题】Who firstly advances the theory of quantization that is applied in the filed of atomic structure for explaining the stability of atoms?
A.
Dalton
B.
Einstein
C.
Bohr
D.
Plonk
【简答题】公路桥涵结构按承载能力极限状态设计时,应采用以下三种作用效应组合____、____、____。公路桥涵结构按正常使用极限状态设计时,应采用以下两种作用效应组合:____、____。
【判断题】In the process of image sampling and quantization, inadequate quantization levels may cause the false contour.
A.
正确
B.
错误
【简答题】Bohr效应
【单选题】— Is that man（男人） his uncle? —_________．
A.
Yes, he is
B.
Yes, it is
C.
No, she isn’t
【单选题】公路桥涵结构按正常使用极限状态设计时,应采用作用( )组合和( )组合。
A.
效应基本组合和偶然组合
B.
短期效应组合和长期效应组合
C.
效应基本组合和长期效应组合
D.
短期效应组合和偶然组合
【单选题】— He says he has an uncle living in Taiwan. — Nonsense!________, his father doesn't have brothers at all. [ ]
A.
More or less
B.
As a matter of fact
C.
In addition
D.
At least
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