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【单选题】
当波源向着静止的观察者运动时，观察者接收到的波的频率大于波源振动的频率，原因是[]。A.
观察者接收到的波的 波速变大
B.
观察者接收到的波的 波速变小
C.
观察者接收到的波的 波长变大
D.
观察者接收到的波的 波长变小
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举一反三
【单选题】I left them alone, as I felt I was _____. [ ]
A.
in a way
B.
on the way
C.
in the way
D.
in no way
【简答题】___________ adv. in the same way
【简答题】adv. in a way that is opposite to sth.
【单选题】According to the passage, which of the following is NOT true?
A.
Social values play an important role in social change.
B.
Social change is more likely to occur in the material aspects of society.
C.
Social change is more likely to occur if it comes gradually.
D.
Social change tends to meet with more difficulty in basic and emotional aspects of society.
【简答题】There is more than one reason for which you need to hire a business attorney（律师）. It is very important to hire some good attorney for your business especially because of the fact that you will need th...
【简答题】下列叙述正确的是:A. 一个纳米是一米的十亿分之一,则一个纳米是无穷小; B. 无穷小是零; C. 零是唯一可作为无穷小的常数; D. 无穷小是以零为极限的变量;
【简答题】adv. (fml) in a way that is the oppsite of sth
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