题目

如图，直线，，相交于，，，． 求证：平面．  答案：提示：容易证明，． 进而可证平面平面．– Mother’s Day is coming. Don’t forget to give my best wishes to your mother.--________. Thank you very much.A. OK, I won’t B. OK, I will C. Yes, I do D. No, I don’t