A:
B:
C:
D:
如下短句或词语涉及到的知识与光的直线传播无关的是( )
A. She's my mother.
B. I have a happy family.
C. What's this?
D. This is my father.
Rose: ____
Tom: It's a picture (照片) of my family.
Rose: Who's this?
Tom: ____
Rose: Who's she?
Tom: ____ And this is me.
Rose: Are you happy?
Tom: Yes. ____
填上适当的词。
____的枣子 ____的秋天 ____的天空 ____的太阳
点电荷A和B,分别带正电和负电,电荷量分别为4Q和Q,在A、B连线上,如图所示,电场强度为零的地方在( )