题目

洪涝地区的灾民用下列几个步骤将河水转化为可饮用水,以下处理过程顺序合理的是 ①化学沉降(用明矾) ②消毒杀菌    ③自然沉降  ④加热煮沸  A.③②①④       B.③①②④      C.③①④②       D.①③④② 答案:B After gradutation she reached a point in her careet ________ she heeded to decion what to do. [  ] A.that B.what C.which D.where
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