文档介绍:福建医大博士研究生入学英语考试试卷():,B,.(40%)Forthefirsttwo-thirdsofthe20thcentury,,however,andespeciallyinthepublicmind,-productsatwaste-,asaresult,,butchemicalproductsareessentialiftheworld’spopulationistobeclothed,’sreservesoffossilfuels()willeventuallybeexhausted,someassoonasthe21stcentury,,usefulforms,forexample,-term,“chemicalproblemsrequirechemicalsolutions”.-scaleproductionbegins,,calledchlorofluorocarbons(orFreons),,nonflammablegasesandvolat