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1、READINGPASSAGE1Youshouldspendabout20minutesonQuestions1-13,whicharebasedonReadingPassage1below.PullingStringstoBuildPyramidsNooneknowsexactlyhowthepyramidswerebuilt.MarcusChownreckonstheanswercouldbe'hangingintheair'.ThepyramidsofEgyptwerebuiltmorethanthreethousandyearsago,andnoonek
2、nowshow.Theconventionalpictureisthattensofthousandsofslavesdraggedstonesonsledges（第1题答案）.Butthereisnoevidencetobackthisup.NowaCaliforniansoftwareconsultantcalledMaureenClemmonshassuggestedthatkitesmighthavebeeninvolved.WhileperusingabookonthemonumentsofEgypt,shenoticedahieroglyphtha
3、tshowedarowofmenstandinginoddpostures（第2题答案）.Theywereholdingwhatlookedlikeropesthatled,viasomekindofmechanicalsystem,toagiantbirdinthesky.Shewonderedifperhapsthebirdwasactuallyagiantkite,andthemenwereusingittoliftaheavyobject.Intrigued,ClemmonscontactedMortezaGharib,aeronauticsprofe
4、ssorattheCaliforniaInstituteofTechnology.Hewasfascinatedbytheidea.'ComingfromIran,IhaveakeeninterestinMiddleEasternscience,'hesays.HetoowaspuzzledbythepicturethathadsparkedClemmons'sinterest.Theobjectintheskyapparentlyhadwingsfartooshortandwideforabird.‘Thepossibilitycertainlyexiste
5、dthatitwasakite,'hesays.AndsinceheneededasummerprojectforhisstudentEmilioGraff,investigatingthepossibilityofusingkitesasheavyliftersseemedlikeagoodidea.GharibandGraffsetthemselvesthetaskofraisinga4.5-metrestonecolumn圆柱fromhorizontal水平的tovertical,usingnosourceofenergyexceptthewind.（第
6、4题答案）Theirinitiacalculationsandscale-modelwind-tunnelexperimentsconvincedthemtheywouldn'tneedastrongwindtoliftthe33.5-tonnecolumn.Evenamodestforce,ifsustained,overalongtime,woulddo.（第5题答案）Thekeywastouseapulleysystemthatwouldmagnifytheappliedforce.Sotheyriggedupatent-shapedscaffolddi
7、rectlyabovethetipofthehorizontalcolumn,withpulleyssuspendedfromthescaffold'sapex.Theideawasthatasoneendofthecolumnrose,thebasewouldrollacrossthegroundonatrolley.Earlierthisyear,theteamputClemmons'sunlikelytheorytothetest,usinga40-squaremetrerectangularnylonsail.Thekiteliftedthecolum
8、ncleanofftheground.
