真空中有一立方体空间如图,在黑点处固定有电荷量均为q的点电荷,则四幅图中a、b两点电场强度和电势均相同的是[ ]
A.
B.
C.
D.
答案:D
肺结核基本病变的包括()
A.纤维化和钙化
B.空洞
C.干酪样病变
D.渗出
E.增殖
—Both of the skirts are in style this year.
—But I think this one is______.[ ]
A. popular
B. much popular
C. more popular
D. the most popular