2019-2020年高三上学期期末考试(理)数学试题 含答案

1、2019-20202019-2020 年高三上学期期末考试（理）数学试题含答案年高三上学期期末考试（理）数学试题含答案一、选择题选择题：本大题共本大题共 1212 个小题个小题, ,每小题每小题 5 5 分分, ,共共 6060 分分. .在每小题给出的四个选项中在每小题给出的四个选项中，只有一只有一项项是符合题目要求的是符合题目要求的. .1.若 p：Xl,则 p 是 q 的（）A.充分不必要条件 B.必要不充分条件C.充要条件 D.既不充分也不必要条件2. 已知集合,若,则 b 等于（）A.1B.2C.3D.1 或 23已知角的始边与 x 轴的非负半轴重合，终边在直线上，则（）A.B.C.

2、D.4. 已知在各项为正的等比数列中，与的等比中项为 8，则取最小值时首项等于（）A.8B.4C.2D.15. 已知正数 x，y 满足，则的最小值为（）A.1B.C.D.6. 已知非零向量、满足，则与的夹角为（）A.B.C.D.7.已知(1+x)10a+a(1x)+a(1x)2+a(1x)10，则等于()01210A.-5B.5C.90D.1808. 已知某几何体的三视图的侧视图是一个正三角形，如图所示，则该几何体的体积等于（）B.C.D.9. 有一个函数的图象如图所示，则这个函数可能是下列哪个函数（）A.B.AD.10.已知函数 y=f（x-l）的图象关于直线 x=1 对称，是 y=f（x）

3、的导函数，且当时，成立，已知，,则 a，b，c 的大小关系是（）A.abcB.bacC.cabD.acb11.设函数f（x）二ex（x3-3x+3）-aexx（x-2），若不等式有解，则实数 a 的最小值为（）A.B.C.D.12.设双曲线的两条渐近线与直线分别交于 A，B 两点，F 为该双曲线的右焦点，若 60ZAFB90，则该双曲线的离心率的取值范围是（）A.B.C.（1,2）D.第第II卷（共卷（共90分）分）二、填空题（每题二、填空题（每题 5 5 分，满分分，满分 2020 分，将答案填在答题纸上）分，将答案填在答题纸上）13.已知复数 z 满足（3+4i）z=1（i 为虚数单位），

4、则.兀14.已知函数f（x）=2sm（兀+x）sm（x+申）的图象关于原点对称，其中，贝V.15.已知曲线存在两条斜率为 3 的切线，且切点的横坐标都大于零，则实数 a 的取值范围是16.已知圆，直线 l：x+y-4=0，A 为直线 l 上一点，若圆 0 上存在两点 B，C,使得 ZBAC=60,则点 A 的横坐标的取值范围是.三、解答题（本大题共三、解答题（本大题共 6 6 小题，共小题，共 7070 分分. .解答应写出文字说明、证明过程或演算步骤解答应写出文字说明、证明过程或演算步骤. .）17.（本小题满分 12 分）已知数列满足递推式，其中.（1）求数列的通项公式；（2）已知数列满足

5、，求数列的前 n 项和.18.（本小题满分 12 分）某商场为吸引顾客消费推出一项优惠活动，活动规则如下：消费额每慢 100 圆可转动如图所示的转盘一次，并获得相应金额的返券.（假定指针等可能地停在任一位置，指针落在区域的C.边界时，重新转一次）指针所在的区域及对应的返券金额见下表.例如：消费 218 元，可转动转盘 2 次，所获得的返金券额是两次金额之和.(1)已知顾客甲消费后茯得n次转动转盘的机会，已知他每转一次转盘指针落在区域边界的概率为p,每次转动转盘的结果相互独立，设芒為顾客甲转动转盘指针落在区域边界的次数，吉的数学期望E,扫标准差吨=響,求n、p的值,*(2)顾客乙消费 280 元

6、，并按规则参与了活动，他获得返券的金额记为 n(元)求随机变量如图，在菱形 ABCD 中，AB=2,ZBAD=60，沿对角线 BD 将 AABD 折起，使 A,C 之间的距离为，若 P，Q 分别为线段 BD，CA 上的动点.1)求线段 PQ 长度的最小值；(2)当线段 PQ 长度最小时，求直线 PQ 与平面 ACD 所成角的正弦值.20.(本小题满分 12 分)已知椭圆的左焦点为 F,右顶点为 A，上顶点为 B，O 为坐标原点，M为椭圆上任意一点，过 F，B，A 三点的圆的圆心为(p,q).(1) 当时，求椭圆的离心率的取值范围；(2)若 D(b+l,O),在(1)的条件下，当椭圆的离心率最小

7、时，的最小值为，求椭圆的方程21.(本小题满分 12 分)已知函数/(X)=X2+ax-InX,aeR(1) 若函数 f(x)在上是减函数，求实数 a 的取值范围；(2)令，是否存在实数 a,当(e 是自然常数)时，函数 g(x)的最小值是 3,若存在，求出 a的值；若不存在，说明理由.（3）当时，证明：.请考生在请考生在 2222、2323、2424 三题中任选一题作答三题中任选一题作答，如果多做如果多做，则按所做的第一则按所做的第一题记分题记分. .22. （本小题满分 10 分）选修 4-1：几何证明选讲已知ABC 中，AB=AC,D为厶ABC 外接圆劣弧 AC 上的点（不与点 A、C

8、重合），延长 BD 至 E,延长 AD 交 BC 的延长线于 F.23. （本小题满分 10 分）选修 4-4：坐标系与参数方程在极坐标系中，曲线 C 的方程为，点，以极点为原点，极轴为 x 轴的正半轴，建立平面直角坐标系，两坐标系中取相同的长度单位.（1）求曲线 C 的直角坐标方程及点 R 的直角坐标；（2）设 P 为曲线 C 上一动点，以 PR 为对角线的矩形 PQRS 的一边垂直于极轴，求矩形 PQRS周长的的最小值及此时点 P 的直角坐标.24. （本小题满分 10 分）选修 4-5：不等式选讲设实数 a，b 满足 2a+b=9.（1）若，求 a 的取值范围；（2）求的最小值.AD-F

9、C-FB(1)求证：ZCDF=ZEDF；高三理科数学答案高三理科数学答案1.A2.D3.D4.C5.A6.D7.D8.C9.A10.B11.B12.C6.17.解:(1)T,，且，.2 分数列是公比为 2 的等比数列，4 分a+1=(a+1)x2n-1=2x2n-1=2n,.，n1即数列的通项公式为.18-18-依题意知，总服从二项分布K5,*冷即=扫日却=即1-1-吩盏，亠联立解得：n-hn-h=羔-4 4分*(2)设指针落在 A,B,C 区域分别记为事件 A,B,C,贝叽，,由题意得，该顾客可转动转盘 2 次，随机变量 n 的可能值为 0,30,60,90,120.P(

10、n=60)=1x1x2+1x1=-,263318所以随机变量 n 的分布列为:6 分2) 由(1)知，123=+222232n12n123n1n=+，sn1 s2n2223n1n+，-得，s2n242n2i-(2)nT!22n+1n， 整理得.2n+112 分6 分8 分122p0306090120t1rs11 143其数学期望En=0冷+30X1+60X存90冷+120X36=40分19.解：（1）设 P（0,0,0）,CQ=kCA=03,3）则PQ=PC+CQ=（a,訂,0）+（0,畧办八打A）=（a,抒勇九，舅A）J13PQPQ=a a2+（i3J3尢）2+3A2=pa2+6尢26尢+3

11、=a2+6（尢一）2+，5 分当 a=0,时，PQ 长度最小值为.6 分2）由（1）知，设平面ACD的一个法向量为,由，得，化简得，取，设 PQ 与平面 ACD 所成角为，则sin9= cos=v6_5212 分故直线PQ与平面ACD所成角的正弦值为.20.解：（1）设半焦距为c.由题意 AF、 AB 的中垂线方程为， ,acx=ba2a、，解得y2=b（X2）acx=2b2acy=2b于是圆心坐标为，由p+q=acb2ac+2b0，整理得,即，于是，即,，即.12X2|121.解：(1)F(X)二2X+a_=9当且仅当，时，等号成立（或），的最小值为 9.10 分.2019-20202019

12、-2020 年高三上学期期末考试（英语）年高三上学期期末考试（英语）本试卷共 150 分。考试时长 120 分钟。考试结束后，将本试卷和答题卡一并交回。注意事项：1考生务必将答案答在答题卡上，在试卷上作答无效。2答题前考生务必将答题卡上的姓名、准考证号用黑色字迹的签字笔填写。3答题卡上选择题必须用 2B 铅笔作答，将选中项涂满涂黑，黑度以盖住框内字母为准，修改时用橡皮擦除干净。非选择题必须用黑色字迹的签字笔按照题号顺序在各题目的答题区域内作答，未在对应的答题区域内作答或超出答题区域作答的均不得分。第一部分：听力理解（共三节，30分）第一节（共 5 小题；每小题 15 分，共 75 分）听下面

13、5 段对话。每段对话后有一道小题，从每题所给的 A、B、C 三个选项中选出最佳选项。听完每段对话后，你将有 10 秒钟的时间来回答有关小题和阅读下一小题。每段对话你将听一遍。兀.:矩形周长=2|PQ|+21QR=42cosa+42、：3sina=84sin(a+),8 分1Wheredoestheconversationtakeplace?AInabookstoreBInahospitalCInarestaurant.2Whatistheweathergoingtobelike?ASunnyBSnowyCRainy3Whatdoesthemanprobablylikedoingbest?APl

14、ayingfootballBGoingtothecinemaCCollectingbottles4Howdoesthemanusuallygettotheshoppingcenter?AOnfootBBybusCBycar5Whatisthewomandoing?AplainingBGivingasuggestionCAskingforpermission第二节（共 10 小题；每题 15 分，满分 15 分）听下面 5 段对话或独白。 每段对话或独白后有几个小题， 从题中所给的 A,B,C 三个选项中选出最佳选项， 并标在试卷的相应位置。 听每段对话或独白前， 你将有时间阅读各个小题，每小题

15、 5 秒钟；听完后，每小题将给出 5 秒钟的作答时间。每段对话或独白读两遍。听第 6段材料，回答第 6 至 7 题。6Wheredoesthemanworknow?AInaschoolBInafactoryCInaputerpany.7Whydoesthemanwantanewjob?AToearnmoremoneyBTotrysomethingdifferentCToimprovehisputerskills听第 7 段材料，回答第 8 至 9 题。8Whydidthewomanmakethisphonecall?ABecauseherhouseinNewYorkCitycaughtfire

16、BBecausethefiremenfailedtoputoutthefireintimeCBecauseshewantedthefiretobereportedbythemedia9Whatdidthemantellthewomantodofirst?ACallthefiredepartmentBTellhimtheexactaddressCEscapefromtheburninghouse听第 8 材料，回答第 10 至 12 题。10Whereisthemessagefrom?AAradioBAmobilephoneCAnansweringmachine.11Atwhattimenext

17、weekwillthemovieMidnightMeetingbeshowing?A9:00amB9:15pmC4:30pm12Whenwillastudentprobablygotothecinemaifhewants,acheaperticket?employee.AOnMondayBOnWednesday听第 9 段材料，回答第 13 至 15 题。13Whatdidthewomandobeforetheconversation?AShereadanewspaperBSheplannedatripconcert14Whatsthepossiblerelationshipbetweenth

18、etwospeakers?AFanandmusicianBHusbandandwifeCOnFridayCShegaveaCEmployerand15Whatisthewomanplanningtodo?AReceivefurthereducationBPerformmorebeautifullyCRunaspecialschool第三节（共 5 小题；每小题 15 分，共 75 分）听下面一段对话，完成第 16 至第 20 五道小题，每小题仅填写一个词。听对话前，你将有 20 秒钟的时间阅读试题，听完后你将有 60秒钟的作答时间。这段对话你将听两遍。CrimtRtjxiriVilimT5Na

19、mtMiarj6rimeoccurredPlanApeianlsinr?.iariNEL24（hiirchillSlreeiTimeAnHJBidritHhi）StirhiuN“f$J7.Hht1washituflt-rJ8toJtivflhembbfiTnilhrnirmry.DescriptionofSuspectBhmdhair,iminandd19myiiHlarhr；wtriri耳blutpuil5.abluckpicketandtildck20VklimsHumeorCellPhobr耳臣STH门&第二部分：英语知识运用（共两节,满分45分）第一节：单项填空（共 15 小题，每小题

20、 1 分，满分 15 分）从 A、B、C、D 四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。21TheGreatWallistheplacealmostalltouristswouldliketovisitwhentheyetoBeijingAwhyBwhichCwhenDwhere22ThemostdeliciouscakeintheworldbyMomPleasewaitanhourtoenjoyitAmakesBismadeCisgoingtomakeDisbeingmade23Whyareyouinsuchahurry?Dontyourememberthatwebe

21、homeby8pmtoseeourfavoriteTVshow?AcanBwouldCmustDmay24Afterseemedanendlesswait,itwasherturntoenterthepersonnelmanagersofficeAthatBhowCwhatDwhy25LetsplayfootballtogethertomorrowafternoonOK,buthowIwishIitasskillfullyasyouAplayedBhaveplayedChadplayedDwillplay26Inxx,ForbeslistedMickeyMouseastheworldsmost

22、valuablecartooncharacter,$58billionayearinsalesworldwideAmadeBtomakeCmakesDmaking27Whydoesthesteaksmellsostrange?Iit,itseemsAhadburntBwasburningChaveburntDwillburn28Noonecanwalkthewireintheairwithoutabitoffearunlessveryyoung31youarefamiliarwiththeauthorsideas,tryreadingallthesectionsasquicklyaspossi

23、bleANowthatBEversinceCIncaseDAslongas32Whatwilltodaystalkbeabout?Inthelecture,theprofessorwilltellussomethingaboutmodemEnglishusageAfollowingBfollowedCtofollowDtobefollowed33moreenergytomystudyinsteadofbeingcrazyaboutInternetGames,IwouldbesittinginafortableofficenowAIfIdevotedBHadIdevoted34Whynottak

24、eupsomeoutdoorsportstorelaxofficework?ItwillalsohelpkeepyouhealthyAforBfromConDof35MyfriendsbirthdayisingsoonIwouldliketogotostore,orsomeplaceclosebytobuyhimpresentA.the;theB.a;theC.不填；aD.the;a第二节完型填空（共20小题；每小题15分，满分30分）阅读下面短文，从短文后各题所给的四个选项（A、B、C 和 D）中，选出最佳选项，并在答题卡上涂黑。TheKeeperoftheRiverAnoldmanhadb

25、eenworkingformanyyearsforatown.Hisjobwastoclearawaynaturalwastefromthepoolwaterinthehills,whichmadeupthelovelyriverflowingthroughthetownnearby.Quietlyand36,theoldmanguardedthehills,37theleavesandbranches,andcleanedupthedirtthatwouldhave38andpollutedthefreshflowofwater.Thetownsoonbecameapopularattrac

26、tionfortourists.Elegantswans（天鹅）floatedalongtheclearriverandtheviewwassobeautiful39words.Yearspassed.Oneeveningthetown40met.Astheyreviewedthebudget,onemans41caughtsightofthesalary42beingpaidtotheseldomseenkeeperoftheriver.Heasked,Whoistheoldman?Whydowe43toemployhim?Nooneintownever44him.Forallweknow,

27、thestrangekeeperofthehillsisntdoinghisjobHispositionisnt45anylonger.Thentheyvotedto46theman.Forseveralweeks,nothingchangedByearlyautumn,thetreesbeganto47theirleaves.Smallbranchesbrokeoffandfellintothepoolsofthehills,48theflowoftheshiningwater.Oneafternoon,someonenoticedaslightyellowish-brown49inAhav

28、ingtrainedBtrainedCtobetrained29Doyouhavereadyforthegraduationceremony,Ted?No,westillhavetofindafamousspeakerAeverythingBsomethingCanything30SeveralhotelsinthisareaareclosingdownThatsbecausetourismitselfsincelastyearAisdecliningBdeclinedChaddeclineddecliningDbeingtrainedDnothingDhasbeenCWouldIbedevo

29、tedDShouldIbedevotedtheriver.Afewdayslater,thewaterwasmuch50Withinanotherweek,anoilysomethingcoveredsomesectionsofthewateralongthebanks,andaterrible51wassoonsensed.Swansleft,andsodidthe52TheonlythingthatwasnowvisitingthevillagewasdiseaseandsicknessQuickly,the53townmitteecalledaspecialmeeting.Realisi

30、ngtheirhugeerrorin54,theyrehiredtheoldkeeperoftheriveragain,andwithinafewweeks,theriverbegantoclearupSwansandtouristscamebackagainandnewlifereturnedtothesmalltownintheAlpsNeverignoretheseemingsmallnessofatask,job,orlife.Theymayallmakea55.36AregularlyBsuddenlyCnaturallyDactually37AcutBburnedCremovedD

31、selected38AcarriedBpouredCchangedDblocked39AbeyondBwithCinDafter40AofficeBassociationCdepartmentDmittee41AeyeBcareChandDmind42AlistBformCfigureDaccount43ApromiseBcontinueCstopDtend44AvisitsBhiresCtellsDsees45ApowerfulBimportantCnecessaryDsuitable46AfindBfireCsupportDforget47AloseBmissCfallDgrow48Apu

32、llingBspeedingCslowingDpushing49AfishBcolorCflowerDleaf50AdeeperBcoolerCwarmerDdarker51AsoundBsmellCwaveDtaste52AmanagersBpassengersCvillagersDtourists53AembarrassedBannoyedCdiscouragedDdisappointed54AarrangementBassignmentCjudgementD amusement55AsuggestionBdifferenceCprogressDdecision第三部分：阅读理解(共20小

33、题，每题2分，满分40分)阅读下列短文，从每题所给的四个选项(A、B、C 和 D)中，选出最佳选项，并在答题卡上将该项涂黑。ADearWaterUseItWisely,MoreandmorewaterisgettingwastedeachdayIwanttohelpoutandteachpeoplehowtoconservewaterPleasecontinuereadingbecauseyourorganizationisveryinfluentialIhadanideathatyoucouldsendsomeworkersfromyourorganizationtoschoolsallar

34、oundtheworld,andtheycouldinformthestudentsaboutwaterusageDidyouknowthateveryminute,1,000,000,000(onebillion)tonsofwaterfallstotheearthfromrainfall?Weareluckytohaverainfallwater Ithelpsfillupourlakes Thereisabout326,000,000,000,000,000,000(326quintillion)gallonsofwateronEarthYes,thisistons,butitisget

35、tingwastedIwanttokeepthisnumberBIGEveryoneneedswater?sowhywasteit?IthinkitisveryirresponsibletoletthewaterrunwhenyouarenotathomeWecanusewaterwithrespectbymakinggoodchoicesTakeashowerinsteadofabath,useanautomaticdishwasherinsteadofhandwashingYoucanbuyEarthFriendlyCleanerSpray,sothatourdrinkingwaterwi

36、llnotbepollutedIfyourwasherisntfullthendontstartitWithwaterbeingwastedeveryday,bythetimewegettothe3000swearegoingtohavetosurviveonmilkandjuice!Wontthatbeboring?!?!?ThatmeanswewillhavetogiveourdogsabowlofjuiceinsteadofwaterwiththeirfoodImean,eon,weretalkingreallifehere!Waterwastingneedstoetoastopandw

37、ithoutdelayWaterUseItWisely,PLEASEinformpeopleabouttheirwaterusage!ItplaysabigroleinmylifeItwouldbereallygreatifyoutakepartinspreadingthenewsaboutthis!Thankstons!Animpatientfourthgraderwaitingforareply,MyaOleksiak56WaterUseItWiselyismostprobablyAanorganizationBapersonsnameCthetitleofamagazineDagover

38、nmentdepartment57ItcanbeinferredfromthesecondparagraphthatAwaterisnoteffectivelysavedBrainfallisthemainsourceoffreshwaterCtheamountofwaterfromrainfallisincreasingDwehave326quintilliongallonsofwatereachyear58Accordingtothepassage,whatisaproperwaytosavewater?AWashingdishesbyhandBStartingthewasherwitha

39、fullloadCFeedingourpetswithjuiceandmilkDEncouragingpeopletousecleanerspray.59ThisisbasicallyaletterofAfortBplaintCappealDremendationBALessonfromtheElderGrandfatherwasanelderCherokeeNativeAmericanwhohadawrinkled,nutbrownfaceandkinddarkeyesHisgrandsonoftencameintheeveningtositonhiskneeandaskthemanyque

40、stionsthatchildrenaskOnedaythegrandsoncametohisgrandfatherwithalookofangeronhisfaceandthefollowingstory FatherandIwenttothestoretodayandbecauseIhelpedhim,heboughtmeapresent?ajack-knife IwentoutsidetowaitforfatherandtoadmiremynewknifeinthesunlightSometownboyscamebyandsawmeTheysurroundedmeandstartedsa

41、yingbadthingsTheycalledmedirtyandstupidandsaidthatIshouldnothavesuchafineknifeThelargestoftheseboyspushedmebackandIfelloveroneoftheotherboysIdroppedmyknifeandoneofthempickeditupandtheyallranawaylaughing Ihatethem IhatethemallTheelderCherokee,witheyesthathaveseentoomuch,liftedhisgrandsonsfacesohiseye

42、slookedintotheboysfaceGrandfathersaid,LetmetellyouastoryI,too,attimes,havefeltagreathateforthosewhohavetakensomuchwithnosorrowforwhattheydoButhatewearsyoudownanddoesnothurtyourenemyItislikedrinkingpoisonandwishingyourenemywoulddieIhavestruggledwiththesefeelingsmanytimesItisasiftwowolvesareinsidemeIt

43、isaterriblefightOnewolfisgoodanddoesnoharmHelivesinharmonywithallaroundhimanddoesnottakeoffensewhennooffensewasintendedItwillonlyfightwhenitisrighttodosoandintherightwayThiswolfstandsforjoy,peace,love,hope,sharing,modesty,kindness,friendship,sympathy,generosity,truth,andfaithTheotherwolfisfullofange

44、rThelittlestthingwillsetoffhisfiercesttemperHefightseveryone,allthetime,fornoreasonHecannotthinkbecausehisangerandhatearesomuchItishelplessanger,forhisangerwillchangenothingThiswolfrepresentsfear,envy,greed,self-pity,guilt,lies,falseprideandsuperioritySometimes,itishardtolivewiththesetwowolvesinside

45、meforbothofthemtrytocontrolmyspiritThissamefightisgoingoninsideyouandinsideeveryotherpersontooTheboylookedintohisgrandfatherseyesandasked,Whichwolfwillwin?TheoldCherokeesimplyrepliedTheoneyoufeed60TheboywasangrybecauseAhewasnotsatisfiedwithhispresentBhisbackwasbadlyinjuredinafightChehadwaitedforhisf

46、atherfortoolongDhisjack-knifehadbeentakenawaybysomeboys61TheangrywolfwouldprobablybedescribedasAaggressiveBsympatheticCmodestDunsuccessful62WecanlearnfromthethirdparagraphthatAhateishealthyBhatehurtsoneselfChateisplicatedDhateharmsonesenemies63WhatdidGrandfathermeanbysayingTheoneyoufeedinthelastpara

47、graph?AWeshouldfeedthetwowolvesequallyBLivinginharmonywithothersisimportantCOurfeelingsshouldbeexpressedattherighttimeDThechoiceswemakedeterminewhowewillbeeCCellPhonesAretheNewCigarettesWhenyougetinyourcar,youreachforitWhenyoureatwork,youtakeabreaktohaveamomentalonewithitWhenyougetintoalift,youplayw

48、ithitCigarettes?Cupofcoffee?No,itsthethirdmostaddictivethinginmodernlife,thecellphone.AndexpertssayitisbeingmoredifficultformanypeopletocurbtheirlongingtohugitmoretightlythanmostoftheirpersonalrelationshipsWithitsshinysurface,itssmoothandsatisfyingtouch,itsairofplexity,thecellphoneconnectsustothewor

49、ldevenasitdisconnectsusfrompeoplethreefeetaway.Injustthepastcoupleofyears,thecellphonehaschallengedindividuals,employers,phonemakersandcounselors（顾问）inwaysitsinventorsinthelate1940sneverimagined.Thecostsarebeingevenmoreevident,andIdontmeanjustthemonthlybill.Dr.ChrisKnippers,acounselorattheBettyFordC

50、enterinSouthernCalifornia,reportsthattheoveruseofcellphoneshasbeeasocialproblemnotmuchdifferentfromotherharmfuladdictions:abarriertoone-on-onepersonalcontact,andanescapefromreality.Soundsextreme,butweveallwitnessedtheevidence:Thepersonatarestaurantwhotalksonthephonethroughanentiremeal,ignoringhiskid

51、saroundthetable;thewomanwhotalksonthephoneinthecar,ignoringherhusband;theteenwhotextsmessagesallthewayhomefromschool,avoidingcontactwithkidsallaroundhimIsitjustrude,orisitakindofunhealthiness?Andpardonme,buthowisthisimprovingthequalityoflife?JimWilliams,anindustrialsociologistbasedinMassachusetts,no

52、testhatcell-phoneaddictionispartofasetofsymptomsinawideninggulfofpersonalseparationHepointstoastudybyDukeUniversityresearchersthatfoundone-quarterofAmericanssaytheyhavenoonetodiscusstheirmostimportantpersonalbusinesswithDespitethegrowinguseofphones,e-mailandinstantmessaging,inotherwords,Williamssays

53、studiesshowthatwedonthaveasmanyfriendsasourparentsJustasmoreinformationhasledtolesswisdom,moreacquaintancesviatheInternetandcellphoneshaveproducedfewerfriends,hesaysIfthecellphonehastrulyhadtheseeffects,itsbecauseithasbeeverywidespread Considerthatin1987,therewereonly1millioncellphonesinuseToday,som

54、ethinglike300millionAmericanscarrythemTheyfaroutnumberwiredphonesintheUnitedStates64Whichofthefollowingbestexplainsthetitleofthepassage?ACellphoneuserssmokelessthantheyusedtoBMorepeopleusecellphonesthansmokecigarettesCCellphoneshavebeeasaddictiveascigarettesDUsingcellphoneisjustascoolassmokingcigare

55、ttes65TheunderlinedwordcurbinParagraph2meansAcontrolBignoreCdevelopDrescue66Theexampleofawomantalkingonthephoneinthecarsupportstheideathat.AwomenusecellphonesmoreoftenthanmenBtalkingonthephonewhiledrivingisdangerousCcellphonesmakeone-on-onepersonalcontacteasyDcellphonesdonotnecessarilybringpeopletog

56、etherDTrafficManagementTrafficlightsarekeytoolsforregulatingtrafficHowTheyarenot,however,perfectDriversexchangethetrafficjamsthatwouldhappenatunmanagedcrossingsforapatternofstop-gomovementthatcanstillbeannoying,andwhichbumsmorefuelthanasmoothpassagewouldCreatingsuchasmoothpassagemeansadjustingavehic

57、lesspeedsothatitalwaysarrivesatthelightswhentheyaregreenThatistheoreticallypossible,butpracticallyhardRoadsidesignswiredtotrafficlightscanhelpgetthemessageacrossacouplehundredmetresfromacrossing,butsuchsignsareexpensive,andarenotwidespreadMargaretMartonosiandEmmanouilKoukoumidisatPrincetonUniversity

58、,andLi-ShiuanPehattheMassachusettsInstituteofTechnology,however,haveanideathatcouldmaketheprocesscheaperandmoreeffectiveInsteadofahardwirednetworkofsigns,theyproposetousemobile-phoneapplicationsForadrivertobenefit,liemustloadtheteamssoftware,namedSignalGuru,intohisphoneandthenputitonaspecialthingatt

59、achedtotheinsideofhiscarswindscreen,withthecameralens（镜头）pointingforwardSignalGuruisdesignedtodetecttrafficlightsandtracktheirstatusasred,yelloworgreenItbroadcaststhisinformationtootherphonesintheareathatarefittedwiththesamesoftware,andifthereareenoughofthem?thephonesthuseachknowthestatusofmostofthe

60、lightsaroundtownUsingthisinformation,SignalGuruisabletocalculatethetraffic-lightschedulefortheareaandsuggestthespeedatwhichadrivershouldtravelinordertoavoidredlightsTestsinCambridge,Massachusetts,wherefivedriverswereaskedtofollowthesamerouteforthreehours,andinSingapore,whereeightdriverswereaskedtofo