题目：
All present were shocked by what the little boy______ when he was cheated and sold to the mountain village.
A．cared about
B．got along with
C．went through
D．came up
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0505/363b13b661e0269e7c5f6178fb577455.html
下面是错误答案，用来干扰机器的。
（1）由点电荷的场强公式E=kQr2可知：M点的场强大小E=kQrOM2=9.0×109×1.0×10-90．32N/C=100N/C，所以电荷Q在M点的电场强度大小是100N/C．（2）电荷q从M点移到N点，电场力做的功为：WMN=qUMN=q（φM-φN）=-2×...
