向某无色溶液中加入过量的稀盐酸有沉淀生成，过滤后向滤液中加入过量的纯碱溶液又有沉淀生成，下列溶液中符合此条件的是(　　)

①Ag^＋、Fe^3＋、Na^＋　②Ag^＋、Al^3＋、K^＋　③Ag^＋、Ba^2＋、NO　④SiO、AlO、K^＋　⑤Ag^＋、NH、H^＋　⑥AlO、K^＋、Ba^2＋

增加：在缺词处加一个漏字符号（∧），并在此符号下面写出该加的词。

删除：把多余的词用斜线（＼）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1).每处错误及其修改均仅限一词；

2).只允许修改10处，多者（从第11处起）不计分。

    In a freezing cold day in January 1994,Jiesang Suonandajie found what he was looking for—a group of poacher who were killing the endangered Tibetan antelope.Jiesang knows he had to move quickly.He shouted to the poachers to put away their guns.Although being surprised,the poachers had a advantage there were more of them.In the battle what followed Jiesang was shot and killed.When its frozen body was found hours late,he was still holding his gun. He had given his life save the Tibetan antelope.

鲁博士公休仪
公仪休者，鲁博士也。以高第①为鲁相。奉法循理，无所变更，百官自正。使食禄者不得与下民争利，受大者不得取小。
客有遗相鱼者，相不受。客曰：“闻君嗜鱼，遗君鱼，何故不受也？”相曰：“以嗜鱼，故不受也。今为相，能自给鱼；今受鱼而免，谁复给我鱼者？吾故不受也。”
【注释】①高第：考试及考核官吏成绩优等。

命题“若$a^2+b^2$≠$0$，则$a=0$且$b=0$”的逆否命题是(  )