A：初一
B：初八
C：十五
如图所示，球A在斜面上，被竖直挡板挡住而处于静止状态，关于球A所受的弹力，以下说法正确的是（ ）
事情已经发展到双方家长被叫来的阶段。
The incident had reached to a ____ ____ both their parents were to be called in.
某班抽取6名同学参加体能测试，成绩如下:80，90，75，75，80，80．下列表述错误的是（ ）
