- 問題詳情:Howtodealwithwastehasbeenaproblemsincehumansstartedproducingit.Asmoreandmorepeoplechoosetoliveclosetogetherincities,thewaste-disposal(處理)problembecomesincreasinglydifficult.Duringtheeighteenthcentury,itwasusualforseveralneighboringtownstogett...
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