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英语六级阅读题英语六级阅读题范文Ourpropheciesneednotbecompletelywildguesses.Weknowsciencehasmovedforwardrapidlyinthepast50yearsandwillcontinuetodoso.Ifweallowourimaginationstobeguidedbyknownresearch,ourpropheciesneednotbesheerfantasy.WedonthavetogosofarastopredictthattherewillbeinvasionbymenfromMars,orthatallfoodandnourishmentwillbetakenincapsuleform,orthatmechanicalmenwillroamtheworld.Withthescientificinformationthatwehaveavailablenow,letsmakeanestimateofprogressinairtravel.Itislikelythatwithin50yearsweshalltravelthroughtheairataspeedof10,000milesperhour.Toofast?Notatall.Jet-propelledplanescannowtravelatleast1,000milesanhour,andjetplaneswillbeoutmodedshortlybyguidedmissiles.TheX-15rocketsspeedin1961was3,690milesperhour,andscientistsarehopingtodoubleandeventriplethisspeed.Theywillaccomplishthisspeed-up,becausethereisnoapparentscientificobstacletopreventit.Someday,certainaerodynamicproblemswillbeovercomeandmissileswillbeenlargedtocarryatleast25passengers.Whenscientistshavesolvedalltheproblemsofconstructingandincreasingthespeedofapparatus-carryingmissiles,theirskillwillleadthemtothenextstepmissilesforinterplanetaryflight.Thispredictionisascientificpossibilityinthenearfuture.FlightsintoouterspacebeganwhenSputnikIwaslaunchedin1957,andmanfirstwentintospacein1961.Duringthelate1950sandearly1960smanysatellitesman-madeastralbodiesorbitedtheearthandmoon.Satellites,whichwillbecontrolledbymenonearth,mayhavemanybeneficialuses.Perhapsscientistswilldiscoverasourceofenergy100milesabovetheearth.Thisenergycouldbetransmittedtousasasourceofpowerformanufacturingplantsorevenforourcookstoves.Oroneofthesemissilesmightserveasthemediumfortransmittingcommunicationsacrosstheglobe.Telephoniccommunicationsmightbecarriedonbybeamingwavesatthemissile,whichwouldinturnbeamwavesatatelephonehalfwayacrosstheworld.Themissilemightbethetelephonicconnection,forexample,betweenyouinNewYork,andafriendinBangkok.Suchasatellitemightalsobeusedasthetransmittingmediumforinterna?tionaltelevisionbroadcasts.Programsbeingtelecastfrom
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