方程组 $\{\begin{array}{l}x+2y=5\\ 3x-2y=7\end{array}$ 的解是____

许多同学进入初中后,对初中的学习生活有各种不同的感受,其中最关键的是（   ）

阅读以上短文，完成下面各题，每空一词。

（A）

    My ideal schoo lis not far from my home. It takes me 15 minutes to walk there. In the school, there are a lot of trees and flowers. It's very beautiful. We also have a big school library, a swimming pool and seven computer rooms. We begin our classes at 8:00 a.m. and finish them at 4:00 p.m. So we have a lot of time for after-school activities. Every day we only do our homework for an hour. Every month we can go on a school trip. How wonderful the school life is!

截面积为0.2m²的100匝圆形线圈A处在匀强磁场中，磁场方向垂直线圈平面向里，如图所示，磁感应强度正按 $\frac{△B}{△t}$ =0.02T/s的规律均匀减小，开始时S未闭合．R₁=4Ω，R₂=6Ω，C=30µF，线圈内阻不计．求：

下列结论一定正确的是（   ）