题目

下面图1中,哪一幅图正确表示了光从空气进入水的光路?(   ) 答案:34、B28、The greater population is living in a city,______ for water, transportation, and disposal of rubbish. A. there is need the greater                                B. the greater need there is C. the greater need is there                                D. there is the greater need
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