皮皮学，免费搜题
登录
搜题
【多选题】
下列关于多普勒效应的说法中,正确的是 ( )A.
只要波源在运动，就一定能观察到多普勒效应
B.
如果声源静止，就观察不到多普勒效应
C.
当声源朝着观察者运动时，声源的频率不变
D.
当声源远离观察者运动时，观察者接收到的频率变低
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【单选题】--- Could you finish your paper today? --- ___________.
A.
I’ve got some paper
B.
That’s great
C.
OK, thank you
D.
Oh, no problem
【单选题】I have done much of the work,could you finish _____ in two days?
A.
the rest
B.
the other
C.
another
D.
the others
【单选题】Could you finish the task in two days? I have something else to do these days.
A.
I could not
B.
Yes.I think so
C.
I'm afraid so
D.
I'm afraid not
【简答题】一批产品中,一、二、三等品率分别为0.8、 0.16、 0.04,若规定一、二等品为合格品,则产品的合格率为
【单选题】符合正常骨产道特点的是
A.
入口平面前后径比横径长
B.
出口平面横径比前后径长
C.
入口平面的横径是骨盆各平面最短的横径
D.
正常骨盆倾斜度为45°
E.
骨盆轴的上段向下向后，中段向下，下段向下向前
【单选题】Could you finish the task in two days?_____
A.
I'm afraind not
B.
I'm afraid so
C.
yes, I think so
D.
I could not
【单选题】—Could you finish the task in two days? —_______. I have something else to do these days. [ ]
A.
I could not
B.
Yes, I thinks so
C.
I'm afraid so
D.
I'm afraid not
【单选题】Could you finish the task in two days? 一（）I have something else to do these days．
A.
I could not
B.
Yes．I think so
C.
I'm afraid so
D.
I'm afraid not
相关题目：
参考解析：
知识点：
题目纠错 0
发布
