已知在硝酸溶液中加入铝粉不产生氢气。若在加入铝粉能放出氢气的无色溶液中，分别加入下列各组离子，可能大量共存的是（  ）

《中华人民共和国未成年人保护法》规定：学校不得使未成年学生在危及人身安全的校舍和教学设施中活动。这体现了对未成年人的（   ）

如图是一根曲杆，可绕O点转动，C点处悬挂着一个物体．若在A点施加一个最小的力使杠杆在图示位置平衡，请画出这个力F和它的力臂．

在等式y=kx+b中，当x=2时，y=﹣4；当x=﹣2时，y=8，则这个等式是（   ）

用所给动词的正确形式填空。
    Be sure ____ (go) to this exhibition at the Sunshine Gallery. Ms. Wang ____ (consider) to be one of the best known Chinese photographers in the world today, and some of her most famous photos are in this exhibition. Ms. Wang ____ (get) to Sunshine Town yesterday afternoon. She really____ (have) something for everyone.  There are many great photos of the countryside. Maybe you ____ (see) some of them on TV before.  It's quite different when you see the real photos. Whatever you do, ____ (not miss) this exhibition!