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已知函数f(x)=lnx﹣. (1)讨论f(x)的单调性,并证明f(x)有且仅有两个零点; (2)设x0是f(x)的一个零点,证明曲线y=lnx在点A(x0,lnx0)处的切线也是曲线y=ex的...
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高三下学期数学《》真题及答案
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已知集合A={x|x>﹣1}B={x|x<2}则A∩B=
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已知三棱锥的三视图如图所示则该三棱锥外接球的表面积为
如图长方体ABCD﹣A1B1C1D1的底面ABCD是正方形点E在棱AA1上BE⊥EC1. 1证明BE⊥平面EB1C1 2若AE=A1EAB=3求四棱锥E﹣BB1C1C的体积.
阅读下面短文根据所给情节进行续写使之构成一个完整的故事.WhenIarrivedat6a.m.inthelargehospitalkitchenRosewasalreadycheckingnametagsonthetrays托盘.HiI'mJanet.'ItriedtosoundcheerfulalthoughIalreadyknewRose'sreputationforbeingimpossibletoworkwith.'I'mscheduledtoworkwithyouthisweek.'Rosestoppedwhatshewasdoingandpeeredoverherreadingglasses.Icouldtellfromherexpressionshewasn'tpleasedtosecastudentworker.'Whatdoyouwantmetodo?Startthecoffee?'Iasked.Rosecoldlynoddedandwentbacktocheckingnametags.Ifilledthe40﹣cuppotwithwaterandbeganmakingthecoffeewhenRoseyelled'That'snotthewaytomakecoffee.'Shesteppedinandtookover.NothingIdidpleasedher.Allmorninghereagleeyesmissednothingandhersharpwordshurt.TotallyexhaustedItrudgedthesixblockshomelatethatJuneafternoon.AsathirdyearuniversitystudentworkingmywaythroughschoolIhadneverbeforemetanyonelikeRose.FightingbacktearsIwrestledwithmydilemmaaloneinmyroom.'WhatshallIdo?'Theanswercaughtmecompletelybysurprise.IneededtoloveRose.WorkingwithRosethenextmorningIignoredthehurtfulremarksthrowninmydirectionanddidthingsRose'swayasmuchaspossible.AsIworkedIsilentlybegantosurroundRosewithawarmblanketoflove.Overthenextfewdaysanamazingthingbegantohappen.MyfocusshiftedfromwhatshewasdoingtomeandIstartedseeingRoseasthehurtingpersonshewas.Thenhericytensionbegantomeltaway.Throughouttherestofthesummerwehadnumerousopportunitiestoworktogether.Eachtimesheseemedtrulyhappytoseeme.Herbitternessgavewayasshestartedopeningup.AsIworkedwiththislonelywomanIlistenedtohersomethingnooneelsehaddone.Ilearnedthatshewasburdenedbyelderlyparentswhoneededhercareandherownhealthproblems.ThedaysslippedbyquicklyasIfinishedthelastseveralweeksofmysummerjob.Isoonwouldbereturningasafull﹣timeuniversitystudentandsaygoodbyetoRose.注意1.所续写短文的词数应为150左右2.应使用5个以上短文中标有下划线的关键词语3.续写部分分为两段每段的开头语已为你写好4.续写完成后请用下划线标出你所使用的关键词语.Paragraph1OnedaywhileIwasworkingaloneinoneofthehospitalkitchensRoseenteredtheroom.Paragraph2AlthoughIneversawRoseagainIstillrememberhervividly.
Neitherstyleofthinkingisbetterorworsethantheotherthey'rejustdifferentasProfessorAnkushChopraexplains.Tobeagreatartistmusicianorbig﹣picturethinkerholisticthinkingisimportant﹣it'saboutcontextandintuition直觉isimportant.Manycareerslikethoseinscienceorlawrewardanalyticthinkingwhichlooksatpartsandunitsandisspecificandlogical.Ofcoursethemostsuccessfulpeoplewillbeabletodobothkindsofthinkingthoughgenerallyholisticthinkinglinkedtocreativityismoredifficulttoteachthananalyticthinking. Sothosepeoplewhoareanalyticthinkerswillseeapriceof$1.99bylookingatthesinglenumbersandwillprioritizethefirstnumberwhenitcomestoprice.Holisticthinkerstendtoviewallpricenumbersasawholeandarelesslikelytobeaffectedbythenine﹣endingpriceeffectLingjiangLoraTuPh.D.professorofmarketingatBaylorandastudy'sleadauthortoldPhys.org. Howeverthatthetypeofthinkingallowsholisticthinkerstoseethewholeratherthanthepartsgoesoutthewindowwhenthey'restressedordistracted分心的. Ourfindingssuggestthatregardlessofconsumers'thinkingstylenine﹣endingpricesaremostlikelytobeeffectiveinsituationsthatoveruseconsumers'resourcessuchaswhenshoppersaretime﹣pressuredatthecheckoutcounterordistractedbybackgroundmusicoroccupiedwithaninteractiveproductdemonstrationTusaid. Thisstudywasdonewiththeideathatmarketersshouldknowaboutthesedifferencesinthinkingstyleandkeeptheminmindwhenthey'repricingthingsfordifferenttypesofpeople.Butanyonewhobuysthingscanbenefittoobyfiguringoutwhatkindofthinkeryouareandthenkeepingthatinmindwhenthesignsshowsalewithaloudnoise!﹣andremindingyourselfthatnobodymakesthebestdecisionswhenthey'redistracted. 1Whichofthefollowingcanbethebestexampleofholisticthinking? A.OnlyifthewholethingmakessensecanJackconcentrateondetails. B.InAmericanshopsyoucanfindmanythingswithnine﹣endingprices. C.Jackkeptonworkingononethingandfinallyachievedgreatsuccess. D.Understandingeachparagraphleadstounderstandingthewholepassage. 2TheunderlinedwordprioritizeinPara.2mostprobablymeans. A.takenonoticeof… B.treat…equally C.thinkof…thetrickiest D.consider…themostimportant 3Accordingtothepassageaconsumershouldrememberthat. A.thenine﹣endingpricescanequallyaffectanytypeofconsumer B.pricingthingsfordifferenttypesofpeoplebenefitscustomers C.backgroundmusicisn'talwaystocreateapleasantatmosphere D.it'simpossibletoaffecthimevenifhe'sdistractedorstressed 4Fromthepassageweknowthat. A.differentthinkingstylescreatedifferentpricingsystems B.preferenceofpricingsystemcanindicatethinkingstyle C.holisticthinkingsomewhatoutweighsanalyticthinking D.bothstylesofthinkingcannotbebeneficialtoonecareer
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已知复数z满足2-iZ=|3+4i|则Z=
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阅读下面短文根据其内容写一篇60词左右的内容概要.Parentseverywherepraisetheirkids.JennBermanauthorofTheAtoZGuidetoRaisingHappyandConfidentKidssays'We'vegonetotheoppositeextremeofafewdecadesagowhenparentstendedtobemorestrict.'Bygivingkidsalotofpraiseparentsthinkthey'rebuildingtheirchildren'sconfidencewheninfactitmaybejusttheopposite.Toomuchpraisecanbackfireandwhengiveninawaythat'sinsinceremakekidsafraidtotrynewthingsortakeariskforfearofnotbeingabletostayontopwheretheirparents'praisehasputthem.Stilldon'tgotoofarintheotherdirection.Notgivingenoughpraisecanbejustasdamagingasgivingtoomuch.Kidswillfeellikethey'renotgoodenoughorthatyoudon'tcareandasaresultmayseenopointintryinghardfortheiraccomplishments.Sowhatistherightamountofpraise?Expertssaythatthequalityofpraiseismoreimportantthanthequantity.Ifpraiseissincereandfocusedontheeffortnottheoutcomeyoucangiveitasoftenasyourchilddoessomethingthatdeservesaverbalreward.'Weshouldespeciallyrecognizeourchildren'seffortstopushthemselvesandworkhardtoachieveagoal'saysDonahueauthorofParentingWithoutFearLettingGoofWorryandFocusingonWhatReallyMatters.'Onethingtorememberisthatit'stheprocessnottheendproductthatmatters.'Yoursonmaynotbethebestbasketballplayeronhisteam.Butifhe'soutthereeverydayandplayinghardyoushouldpraisehiseffortregardlessofwhetherhisteamwinsorloses.Praisingtheeffortandnottheoutcomecanalsomeanrecognizingyourchildwhenshehasworkedhardtocleantheyardcookdinnerorfinishabookreport.Butwhateveritispraiseshouldbegivenonacase﹣by﹣casebasisandbeproportionate相称的totheamountofeffortyourchildhasputintoit.
若变量xy满足约束条件则z=3x﹣y的最大值是.
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We'veallhadcaseswherewe'vewaitedjustabittoolongtopayanelectricbillorspeedingticket.ButonemanfromCaliforniabyreasonableassumptionwhogoesbyDaverecentlytookprocrastination拖延onestepfurtherbypayingaparkingticketalmostahalf﹣centuryafteritwasgiven. InDecember2018theMinersvillePoliceDepartmentinPennsylvaniareceivedaletterinthemail.WhoeverwrotetheletterdecideditwasbesttokeephisnamesomewhatunknownsoheputthereturnaddressasWaywardRoadAnytownCaliforniaunderthenameFeelingguilty. Whentheofficersopenedtheenvelopetheyfoundabriefletteralongwitha$5billandaparkingticketdatingallthewaybackto1974.ThenotereadDearPDI'vebeencarryingthisticketaroundfor40plusyearsalwaysintendingtopay.ForgivemeifIdon'tgiveyoumyinfo.WithrespectDave. Eventhoughtheinitialparkingticketwasonlyfor$2Davemusthavefeltawfullyguiltybecauseheleft150percentor$3ininterest. MichaelCombsthePoliceChiefoftheMinersvillePoliceDepartmentstatedinaninterviewthatthesameticketwouldcostabout$20ifitwasgiventoday.Combswentontosharethattheoriginalticketfrom1974wasgiventoavehiclethathadanOhiolicenseplate. Becausetherewasnosystemfortrackingticketsgiventoout﹣of﹣statecarsbackthenDavecouldhavegottenawaywithneverpayingthe$2fine.Butapparentlyguiltgotthebestofhimandhedecidedtofinallycoughupthemoneymorethan40yearspastitsduedate. 1HowmuchdoweknowaboutDave? A.HelivesinWaywardRoadAnytownCalifornia. B.Thepolicearetryingtofindoutmoreabouthim. C.HiscarprobablycamefromOhioatthattime. D.Daveisofcoursetheman'srealnameindeed. 2Whydidn'tDavepayfortheparkingticketuntilrecently? A.Hecompletelyforgotaboutitinthepast44years. B.Hedidn'tfindituntilalmosthalfacenturylater. C.Hefailedtofindoutwhoheshouldpaythemoneyto. D.Hedidn'tpayforitjustbecauseofprocrastination. 3WhatdroveDavetopayfortheparkingticketatlast? A.Astrongsenseofguilty. B.Fearofbeingtrackedbythepolice. C.Worryaboutbeingfinedmore. D.Suddenchangeofhisfinancialsituation. 4Whichofthefollowingcanbethebesttitle? A.PoliceChiefoftheMinersvillePoliceDepartmentSharesaStory B.MysteriousProcrastinatorFinallyPays44﹣Year﹣OldParkingTicket C.UnusualLetterComesfromWaywardRoadAnytownCalifornia D.ParkingTicketCarriedAroundforAlmostHalfaCenturyfromOhio
若抛物线y2=2pxp>0的焦点是椭圆+=1的一个焦点则p=
ChinaisknownastheKingdomofBamboo.Morethan400speciesofbambooonethirdofallknownspeciesintheworldgrowinChina.China1leadtheworldintheamountofareaplantedwithbamboothenumberofbambootreesandtheamountofbamboowood2produceeveryyear. Theoldestbamboo3articleinChinawereunearthedfromtheremainsofaprimitivesocietythatexistedsome7000yearsagoin4isnowHemuduYuyaoCountyZhejiangProvince.AsearlyastheShangDynastyChinesepeopleusedthebambooformakingweaponssuchasbowsandarrows.Beforepaper5inventstripsofbamboowerethemostimportantwritingmediummorewidelyusedthansilk6theywerecheaperresistanttocorrosion腐蚀andmoreabundant.BamboohasthusplayedanimportantpartinthespreadanddevelopmentoftraditionalChineseculture. Bamboowas7closeconnectedwiththedailylivesofpeopleinancientChina.SuDongpoaliterarygiantoftheSongDynastysaidthatpeoplecouldnotlive8bamboo andpeopleofthetimeusedbamboo9makepaperhatsshoesandsoon.Atthattimeastodaybambooshootswereeatenasapopulardishbecauseof10theycrispnessandfreshsweettaste.Bambooshootsalsocontainvitaminssugarfatandprotein.
Hereallydidlooklikeatouristwithacameraaroundhisneckandabottleofsunscreenstickingoutofhisbag. Thefatmansatontheterrace草坪drinkinglemonadealittlebiteachtimeand1tolookatasmoothandshinycruisebrochure.Hissunglasses2hiseyesbutIknewhewasn'tlookingatthebrochurehehadn'tturneda3forthelasttenminutes. AsIbroughthimwhathehadorderedhecoughedupathankyouandlookedatme4.Itriednottostareatthetinyscaracrosshislefteyebrow. Iwalkedbackinsidewithmy5tray托盘shakingmyhead.Helooked6butIcouldn'tquiteplacehim. Thenit7me.Thecaraccident.The8strangerwhohelpedmeoutofmysmashedcar9beforeitexploded.I10backtohistable. Hewasgone. Imovedhissaucerandfoundhistipalongwitha11 Iamdeeply12toyou.ThenightofyourcaraccidentIwasonmywayto13ajewelrystore.Savingyour14broughtthingsbackinperspective看法.Inowliveanhonestlifethankstoyou.Godblessyou!Mr.D. Itrembled.ThenightofmycaraccidentIwas15foraninterviewinashadydanceclub.Seeinghumankindnessthroughhis16gestureturnedmylifearoundandbrought17backintomylife. I18thetipheleft.Amongtheone﹣dollarnoteswasa100﹣dollarnotewithapenmark19InGodWeTrustwhichfirstappearedonpapermoneyin1957. Isaidasilent20forhimandgotbacktoworksmiling. 1A.asking B.pretending C.refusing D.burning 2A.masked B.protected C.beautified D.comforted 3A.picture B.bottle C.page D.dish 4A.shyly B.worriedly C.fixedly D.briefly 5A.empty B.clean C.heavy D.new 6A.kind B.familiar C.sad D.puzzled 7A.attracted B.failed C.moved D.hit 8A.funny B.wealthy C.mysterious D.hungry 9A.even B.perhaps C.just D.long 10A.rushed B.inched C.struggled D.danced 11A.book B.card C.notice D.Poster 12A.committed B.attached C.guilty D.grateful 13A.rob B.visit C.help D.manage 14A.money B.face C.life D.Time 15A.waiting B.longing C.heading D.Preparing 16A.friendly B.heroic C.traditional D.Exciting 17A.happiness B.glory C.honesty D.faith 18A.dropped B.doubted C.weighed D.unfolded 19A.colouring B.underlining C.enlarging D.deleting 20A.prayer B.hello C.congratulation D.apology
Rockmusicconsistsofmanydifferentstyles.Eventhoughthereisacommonspiritamongallmusicgroupstheymakeverydifferentmusic.1AtthattimetheBeatlesenteredtheworldofmusicfromLiverpool. AftertheyweregivenaninvitationtoappearliveonBBCtheBeatlesquicklybecamefamousinBritainwithnationwidetours.Bymid﹣1963theBeatleshadbeenextremelypopularinEngland.2Theyheldlargeconcertsandperformedatclubs.TheybecamethehottestthingonthepopmusicsceneinEngland.Theybeganasamodestlysuccessfulmusiciangroupandendedtheyearasshowbusinesslegends传说.JohnLennonandPaulMcCartneywerenamedcomposersoftheyear. 3TheywerenotsurehowtheAmericanswouldreacttothenewtypeofmusic.BeatlemaniahitNewYorkonFebruary71964.Hundredsoffansjammedtheairporttogreetthem.4Theconcertwasbroadcastliveandattractedthelargestonenightaudienceinthehistoryoftelevisionuptothattime.TheBeatlesweredescribedasaBritishinvasion入侵bylocalandnationwidenewspapersatthattime.TheirvictoryinAmericawasstillrememberedasamajorturningpointinthehistoryofrockandroll.ThankstotheBeatlesalotofopportunitieswereopeneduptonewfacesonthemarket.5 A.TheydecidedonatourtotheUnitedStatesin1964. B.Eventheirhairstylesbecamemajortrendsatthattime. C.Rockmusicdevelopedinthe1950sandtheearly1960s. D.Howevertheirsongschangedthelivesofgenerationstocome. E.ManyrockbandswereabletofollowinthefootstepsoftheBeatles. F.TheyappearedinthefilmsAHardDay'sNight1964andHelp!1965. G.TheyperformedtheirfirstconcertinAmericaatCBStelevision's53rdstreetstudio.
LearntoManageYourTimeinCollege Acommonviewbothamongandofcollegestudentsisthattheyarealwaysshortonmoney.Whilethismaybetruemanycollegestudentsarealsoalwaysrunningshortonsomethingelsetime.1Hereareafewthingstoconsider Manageyouracademictime.2Consequentlyyouracademicworkshouldalwayscomefirstwhenitcomestoarrangingyourtimeinorderofimportance.Whenlookingatyourschedulefortheweekfigureoutwhatyouracademiccommitmentslooklike.Whattimedoyouhaveclasses?Howmuchhomeworkdoyouhavetodo?Whatassignmentsaredue?Whendoyouhavemajorexamsorquizzes? Manageyourpersonaltime.Itsanunrealisticexpectationtothinkthatyoucanstudygotoclassandworkalldayeveryday.3Makesuretoallowyourselftimetogotosomethingfunintheyardattendameetingforyourfavoriteclubandjusthangoutforanhourorsoatnightwithfriendsoverdinner.Doingthingsthatmakeyourpersonaltimemoreenjoyableandnottotallyfocusedonschool?canactuallyimproveyourproductivitywhenworkingonprojectslater. Keepyourhealthinmind.Whenpeople'sschedulesaretightoneofthefirstthingstogoissleep.Whileitmaybecommonamongcollegestudentsalackofsleepismorehurtfulthanyoumightthink.Itcanthroweverythingintodisorderyourmentalhealthyourphysicalhealthyourstresslevelandofcourseyourschedule.4 Useyourtechnology.Nothinghelpsacollegestudentstayorganizedmorethanagoodcalendar!SomestudentsusethecalendarsontheirphonesothersusethingslikeGoogleCalendarothersstillusetheclassicpaper﹣calendarmodel.5Justchangeandtryagain. A.Tryyourbesttokeeparoutineonaregularbasis. B.Rememberthatyourbrainneedstohaveabreaktoo. C.Ifwhatyou'reusingisn'tworkingforyoudon'tgiveup. D.Howcanyoubalanceyourtimewhenthereneverseemstobeenoughofit? E.It'simportanttorememberwhyyou'reincollegeinthefirstplacetograduate. F.Makingalistandthencrossingitemsoffastheyarecompletedcanbesatisfying. G.Takemomentstoplanoutthetimeforaweekyourhomeworksocialtimeandsleep.
已知双曲线-=1a>0b>0的左右焦点为F1F2过左焦点F1作垂直于x轴的直线交双曲线的两条渐近线于MN两点若∠MF2N是直角则双曲线的离心率是
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.错误仅涉及一个单词的增加删除或修改.增加在缺词处加一个漏字符号∧并在其下面写出该加的词.删除把多余的词用\划掉.修改在错的词下画一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改均仅限一词 2.只允许修改10处多者从第11处起不计分. Iusedtothinkcooperatingwasteoftimebutonethingchangesmymind.Onedaythescientificteacheraskedustodosomeresearchesandhandedintheconclusion.ThattookmelotsoftimetodotheresearchbutIstillcouldn'tfinishedit.SoItriedtocooperatewithothers.Wesharedourresearchesandthenmadethecompletelyconclusionsoon. SoIthinkcooperatingnotonlysavesourtimesbutalsohelpsustopromotethecommunicationwithothers.Althoughintheworldtodayveryfewthingscanbesuccessfullydonebyjustonepersoncooperatingcanbenefitfrombothorallsides.
TheAmericanHeartAssociationAHAsaysthattoomanypeoplearespendingfartoomuchtimeonchairsandcouches.BasedonexistingevidencewefoundthatU.S.adultsaresedentaryforaboutsixtoeighthoursadaysaidDeborahRohmYoungchairofAHApanelthatwrotethenewadvisory. AccordingtotheAHAgrowingevidenceshowsthatonitsownexerciseisn'tenoughtocancelouttheunhealthyeffectsofsittingforalongtime.RegardlessofhowmuchphysicalactivitysomeonegetslongsedentarytimecouldnegativelyinfluencethehealthofyourheartandbloodvesselsYoungexplained. Theexactmechanismsbehindtheeffectaren'tyetclear.Therearemanyimportantfactorswedon'tunderstandaboutsedentarytimeyetYoungsaid.Shestressedthatthetypesofstudiesavailableidentifytrendsbutdon'tprovecauseandeffect. Wedon'thaveinformationabouthowmuchsedentarybehaviorisbadforhealth﹣thebestadviceatthistimeisto‘sitlessandmovemoresheadded. Howmuchmore?AccordingtotheAHApeopleshouldtrytogetatleast30minutesofmoderatetovigorous剧烈的exerciseadaytoreachtherecommended150minutesofmoderateexerciseor75minutesofvigorousexerciseaweekThat'shealthierthantryingtocramtheirweeklyexerciseintooneortwodaysaccordingtothestatement. TherealrisksimplycomesdowntotheamountwesitwithouttherebeingatruemedicineormethodtocontroltheharmfuleffectssaidSteinbaumapreventivespecialistinheartdisease. Stillsocietyhasevolvedtoencouragesittingsheadded. Ourliveshavebecomefocusedaroundactivitiesrequiringustobestill﹣whetheritbetransportationourcomputersorthetelevisionorcomputerinourleisuretimeSteinbaumsaid.Sociologicallyinsteadofbeingactivetobeproductiveortohaveenjoymentourproductivityandfunoftenrequiresminimalphysicalactivities. 1WhatisthemainpurposeofthenewadvisorydeliveredbyAHA? A.Toadvisepeopletositlessandexercisemore. B.Toexplorethecauseandeffectofinactivebehavior. C.Toanalyzethelinkbetweenhearthealthandexercise. D.Toshowthegeneralsocialtrendofencouragingsilting. 2WhichofthefollowingwouldDeborahRohmYoungmostprobablyagreewith? A.Doingexerciseisofnobenefittothosecouchpotatoes. B.Sittingtoomuchisacontributingfactortoheartdiseases. C.Theexactcausebehindtheeffectoflong﹣timesittingisapparent. D.Thevitalthingforhealthisthetotalamountofweeklyexerciseyoudo. 3AccordingtoSteinbaumtheincreaseofsittingtimeis. A.abasicaspectofpromotingthequalityoflife B.arealriskthatcanberemovedbyvigorousexercise C.anunavoidableconsequenceofsocialdevelopment D.abigchangeinmodempeople'sconceptofhealth
Thereareseveralreasonswhyschooluniformsaregoodidea.Firstofalluniformshelptheschoollooksmart.Thestudentsfeelthattheybelongtoaparticulargroup.Wheneverypupilintheschoolwearstheuniformnobody1havetoworryaboutfashion时尚.Everybodywears2samestyleofclothes.Uniformscanbeusefulinunexpectedways.AschoolinIrelandhasintroducedaninterestingnewuniform.Ontheedgeofthejacketthereisapieceofcloth3givesofflightinthedark.Whenthechildrenarewalkingor4cycletoschoolondarkmorningscardriverscan5easyseethem. Butcanuniformshelpimproveschoolstandards?Theanswer6thisquestionisnotclear.OnestudyinAmericafoundthatstudents'grades7improvealittleaftertheschoolintroduceduniforms.Butsomestudentsdidn'twant8weartheuniform.OtherAmericanstudiesshowedno9connectbetweenuniformsandschoolperformance. Schooluniformsare10traditioninBritainbutsomeschoolsarestartingtogetridofthem.Someverygoodschoolsdon'thaveauniformpolicy.Howeveruniformsarestillpopular.Pupilsatabout90percentofBritishsecondaryschoolswearuniforms.
阅读下面短文根据所给情节进行续写使之构成一个完整的故事.Bobbywasgettingcoldsittingoutinhisbackyardinthesnow.Bobbydidn'twearbootsorratherhedidn'townany.Thethinsneakersheworehadafewholesinthemandtheydidapoorjobofkeepingoutthecold.Bobbyhadbeeninhisbackyardforaboutanhouralready.Tryashemighthecouldnotcomeupwithanideaforhismother'sChristmasgift.Heshookhisheadashethought'Thisisuseless.EvenifIdocomeupwithanideaIdon'thaveanymoneyforagift.'WipingtearsfromhiseyesBobbystartedwalkingdowntothestreetwheretheshopswere.Itwasn'teasybeingsixwithoutafatherparticularlywhenheneededamantotalkto.Bobbywalkedfromshoptoshoplookingintoeachdecoratedwindow.Everythingseemedsobeautifulbutsooutofreach.ItwasstartingtogetdarkandBobbyreluctantlyturnedtowalkhomewhensuddenlyhiseyescaughttheglimmer激光ofthesettingsun'sraysreflectingonsomethingontheroadside.Hereacheddownanddiscoveredashinydime一角硬币.NeverbeforehasanyonefeltaswealthyasBobbydidatthatmoment.Aslieheldhisnewly﹣foundtreasurewarmthspreadthroughouthisentirebodyandhewalkedintothefirststore.Hisexcitementquicklyturnedcoldwhensalespersonaftersalespersontoldhimthathecouldnotbuyanythingwithonlyadime.Hesawaflowershopandwentinsidetowaitinline.WhentheshopowneraskedifhecouldhelphimBobbypresentedthedimeandaskedifhecouldbuyoneflowerforhismother'sChristmasgift.TheshopownerlookedatBobbyandhisonedimeoffering.ThenheputhishandonBobby'sshouldersaying'YoujustwaithereandI'llseewhatIcandoforyou.'AsBobbywaitedhelookedatthebeautifulflowersandeventhoughhewasaboyhecouldseewhymothersandgirlslovedflowers.注意1.所续写短文的词数应为150左右2.应使用5个以上短文中标有下划线的关键词语3.续写部分分为两段每段的开头语己为你写好4.续写完成后请用下划线标出你所使用的关键词语.Paragraph1Afewminuteslatertheshopownercameout.Paragraph2WiththebunchofrosesinhishandsBobbywalkedoutofthedoorandthenbrokeintoarun.
已知α∈02sin2α=cos2α+1则sinα=
Moneywithnostringsattached.It'snotsomethingyouseeeveryday.ButatUnionStationinLosAngeleslastmonthaboardwentupwithdollarbillsattachedtoitwithpinsandasignthatreadGiveWhatYouCanTakeWhatYouNeed. Peoplequicklycaughton.Andwhilemanytookdollarsmanyotherspinnedtheirowncashtotheboard.Peopleofallagesracesandsocio﹣economic社会经济的backgroundsgaveandtooksaidTylerBridgesofTheToolboxwhichcreatedtheproject.Weevenhadabrideinherweddingdresscomeuptotheboardandtakeafewdollars.Mostofthebillsontheboardweresinglesbutafewpeopleleftfivestensandeventwenties.Thevideoclip片段showsonemanwhohadfounda$20billpinningittotheboard. WhatIcansayforthefolksthatgavethemostisthattheywerefullofsmilesBridgessaid.There'sacertainfeelingthatgivingcandoforyouandthatwasapparentinthosethatgavethemost.MostpeoplewhotookdollarstookonlyafewbutBridgessaidaverysmallnumbertookasmuchastheycould. WhiletheclipmightlooklikepartofanewadcampaignBridgessaidtheonlygoalwastoshowgenerosityandsympathy.HeaddedthathehopespeopleinothercitiesmighttrysimilarprojectsandposttheirownvideosontheInternet. Afteralleveryonehasbaddaysandgooddayshesaid.Somedaysyouneedahelpinghandandsomedaysyoucanbetheonegivingthehelpinghand. 1Whatdoestheexpressionmoneywithnostringsattachedinparagraph1mean? A.Moneyspentwithouthesitation. B.Moneynotlegallymade. C.Moneyofferedwithoutconditions. D.Moneynottiedtogether. 2WhatdidBridgeswanttoshowbymentioningthebride? A.Womentendedtobemoresociable. B.Theactivityattractedvariouspeople. C.Economicproblemsweregettingworse. D.Youngcouplesneededfinancialassistance. 3WhydidBridgescarryouttheproject? A.Todoatestonpeople'smorals. B.Toraisemoneyforhiscompany. C.Toearnhimselfagoodreputation. D.Topromotekindnessandsympathy.
已知向量=23=32则|﹣|=
在“一带一路”知识测验后甲乙丙三人对成绩进行预测. 甲我的成绩比乙高. 乙丙的成绩比我和甲的都高. 丙我的成绩比乙高. 成绩公布后三人成绩互不相同且只有一个人预测正确那么三人按成绩由高到低的次序为
△ABC的内角ABC的对边分别为abc.已知bsinA+acosB=0则B=.
已知函数fx=x﹣1lnx﹣x﹣1.证明 1fx存在唯一的极值点 2fx=0有且仅有两个实根且两个实根互为倒数.
设αβ为两个平面则α∥β的充要条件是
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