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在△ABC中，D是BC中点，E是AD中点，BE＝1，点M是平面ABC上的任意一点，则（2）的最小值为（ ）
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高三下学期数学《》真题及答案
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1如图1在△ABC中点M.为BC边的中点且MA=BC求证∠BAC=90°.2如图2直线ab相交于点A
在△ABC中AD是BC边上的中线点E.是AD中点过点E.作垂线交BC于点F.已知BC=10△ABD的
1.2
2.4
3.6
4.8
如图在△ABC中D.是BC边上的中点且AD=ACDE⊥BCDE与AB相交于点E.EC与AD相交于点F
如图在△ABC中AB=AC点D.是BC的中点点E.在AD上求证AD⊥BC证明∵D.是BC的中点∴BD
如图在△ABC中D.是BC的中点且AD＝ACDE⊥BCDE与AB相交于点E.EC与AD相交于点F.1
如图1M.是铁丝AD的中点将该铁丝首尾相接折成△ABC且∠B.=30°∠C.=100°如图2.则下列
点M.在AB上
点M.在BC的中点处
点M.在BC上，且距点B.较近，距点C.较远
点M.在BC上，且距点C.较近，距点B.较远
如图△ABC中D.为BC的中点G.为AD的中点过点G.任作一直线MN分别交ABAC于M.N.两点若
如图在三棱锥P-ABC中PA⊥底面ABC.点D.E.N.分别为棱PAPCBC的中点M.是线段AD的中
19.如图在△ABC中AB=AC点D.是BC的中点点E.在AD上.求证1ΔABD≌ΔACD;2BE=
.如图等腰Rt△ABC中∠BAC=90°AD⊥BC于D.∠ABC的平分线分别交AC.AD于E.F.两
1个
2个
3个
4个
已知:在△ABC中BC>AC动点D.绕△ABC的顶点A.逆时针旋转且AD=BC连接DC.过ABDC的
如图已知等边△ABC中D.是AC的中点E.是BC延长线上的一点且CE=CDDM⊥BC垂足为M.求证M
如图在△ABC中AB=AC点D.是BC的中点点E.在AD上.求证1△ABD≌△ACD2BE=CE.
如图①点M.是铁丝AD的中点将该铁丝首尾相接折成△ABC且∠B.=30°∠C.=100°如图②则下列
点M.在AB上
点M.在BC的中点处
点M.在BC上，且距点B.较近，距点C.较远
点M.在BC上，且距点C.较近，距点B.较远
① ②
如图7△ABC中AB＝4AC＝7M.是BC的中点AD平分∠BAC过M.作MF∥AD交AC于F.则FC
在△ABC中点D.为BC的中点BD=3AD=4AB=5则AC=_
如图1M是铁丝AD的中点将该铁丝首尾相接折成△ABC且∠B=30°∠C=100°如图2.则下列说法正
点M在AB上
点M在BC的中点处
点M在BC上，且距点B较近，距点C较远
点M在BC上，且距点C较近，距点B较远
如图1在四边形ABCD中AB=CDE.F.分别是BCAD的中点连接EF并延长分别与BACD的延长线交
如图在△ABC中D是BC边上的一点E是AD的中点过A点作BC的平行线交CE的延长线于F且AF=BD连
在Rt△ABC中∠ABC=90°D.是BC的中点E.是AD的中点过点A.作AF∥BC交BE的延长线于
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Theideaofrobotrulersfriendsandlovershasbeenatopicofsciencefictionnovelsforyears. Butaccordingtoonemathematicalmodelofhowourbrainscreateconsciousnessemotionalmachineswillneverexist. Thisisbecausecomputerscan'thandleanyprocessthatcompletelyintegrates整合informationsotheycannotbeconsciousorfeeloneexpertsays. AmathematicalmodelforconsciousnessdevelopedbyGiulioTononiattheUniversityofWisconsin﹣Madisonsaysthattheabilitytointegrateinformationisakeyfeatureofconsciousness. Hebelievesthatintegratedinformationcan'tbebrokendownintosmallerpiecesinconsciousmindsbecausethebraincontextualizes将……融入背景information. Forexamplewhenweseearedcircleourbrainsdon'tseetheshapeasacolourlesscircleplusashapelesscolouredareaNewScientistreported.Insteadweseeitasawhole﹣aredcircleweunderstandthewiderpicture. It'seasyenoughformachinestoeditacollectionofindividualimages图象butmemoriesaremadeupofabankofintertwined相互交织的imagesandexperiencesandcannotbechangedinthesameway. Researchershaveusedmathematicstoshowthatcomputerscannothandlethecomplexprocessesneededtofitpiecesofinformationtogetherperfectly. Thereforeifconsciousnessisbasedontheintegrationoflotsofpiecesofinformationcomputerscan'tbeconsciousandcan'texperienceemotionslikehumans. ProfessorPhilMaguireoftheNationalUniversityofIrelandinMaynoothsaysthatconsciousnesscannotbecreatedinaphysicalmachineinlimitedtimeusinglimitedmemory. Itdoesn'tnecessarilymeanthatthereissomemagicgoingoninthebrainthatinvolvessomeforcesthatcan'tbeexplainedphysically.Itisjustsocomplexthatit'sbeyondourabilitiestochangeithesaid. Hisresearchmaymeanthatlonelyhumanswillnotfindlovewitharobottheyareunlikelytobemadetheirslaveseither. 1Whydoexpertsthinkemotionalmachineswon'texist? A.Machinescan'tsolveproblems. B.Machinescan'tintegrateinformation. C.Machinescan'thandleinformation. D.Machinescan'tcommunicatewithpeople. 2TheexamplementionedinParagraph6isusedtoshow. A.machinescannotfeel B.thebrainhasconsciousness C.machinescanrecognizeshapesandcolors D.thebraincancontextualizeinformation 3Itcanbelearnedfromthetextthat. A.theideaofrobotloverswon'tcometrue B.machinescaneditintertwinedimages C.robotscanfitpiecesofinformationtogetherperfectly D.computerscanexperienceemotionslikehumansoneday 4Whatwouldbethebesttitleforthetext? A.Howrobotswork B.Robotswillneverhavefeelings C.Willrobotsbecomepeople'sfriends? D.Whatwillrobotsbelikeinthefuture?
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.每处错误仅涉及一个单同的增加删除或修改. 增加在缺词处加一个漏字符号Ʌ并在其下面写出该加的词. 删除把多余的词用斜线\划掉. 修改在错的词下划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. ThenewschoolyearisaroundcornersoIneedtobuysomethingtomychildrenandmyself.Thereforeyesterday'safternoonItookthemtoashoestoretobuyingsomenewshoes.Myyoungestkidswantedapairofsportsshoesandthusweboughtonepair.Myoldersonneededapairofcasualshoesforschool.andwewerefoundsomeonsale.Thefirstpairwhichhetriedonwasalittlesmall.soheputonotherpair.andtheyfittedhimperfectly.Mydaughterwantedbeautydressshoesandshegotsomehighheels.Imyselfboughtsomebootsbecausemyoldoneswerewearingout.
在“要致富先修路”的思想指导下近几年云南的交通有了快速的变化特别是“高铁网络”延伸到云南以后许多地区的经济和旅游发生了翻天覆地的变化高铁列车也成为人们外出旅行的重要交通工具．假期里小明和爸爸从昆明到某地去旅游从昆明到该地乘汽车行驶的路程约为800km高铁列车比汽车行驶的路程少50km高铁列车比汽车行驶的时间少5h．已知高铁列车的平均时速是汽车平均时速的2.5倍求高铁列车的平均时速．
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假定你是校学生会__李华上周你校组织一个文化交流团到英国某高中进行文化交流现已回国.请你代表你校交流团给英国活动负责人David写一封信内容包括1.感谢对方的招待2.此行的体验和收获3.邀请对方暑假来中国体验中国文化.注意1.字数100左右开头结尾已为你写好不计入总词数2.可以适当增加细节以使行文连贯.DearDavidWehavebeenbackhomesafelyfromEngland.YoursLiHua
如图AB∥CDAD与BC相交于点OCD＝3ABS△ODC＝60则S△OAB＝．
大理古城简称榆城位居风光亮丽的苍山脚下是全国首批历史文化名城之一．它东临洱海西枕苍山城楼雄伟风光优美引来无数旅客前来观光．“十一”期间相关部门对到大理观光的游客的出行方式进行了随机抽样调查整理绘制了两幅统计图尚不完整根据图中信息下列结论错误的是
解不等式组．
Forhealthyadultsexpertssaythateatingalotoffruitisunlikelytogetyouintotroubleaslongasit'spartof1normaldiet. Themainconcernwithovereatingfruitis2itnaturalsugaryetresearchhasalwayslinkedwhole﹣fruiteatingtoa3reduceriskforobesityandotherdiseases.That'sbecausewholefruithasafewbuilt﹣in4advaniagethatseemtoreduceanysugar﹣drivenhealthrisks.Itcontainstwokindsoffiberwhichformabarrierontheinsideofthesmallintestine肠.Thisbarrierlimitstherateofsugarabsorbingsothattheliver肝isnotharmedjustlikestoppingalargewave5buildinganunderwaterwall.Fruitfiberalso6helpfoodreachthefinalpartofyoursmallintestinesoonersoyoutendtofeelfull7quickaftereatingfruit.Asaresultthechancesyouwillovereatfruitarerelativelylow. Somefruitsmaybebetter8eatthanothers.Forexampleberrieshavebeenlinkedtobothbetterheartandbetterbrainhealth.9grapesmayneedmoreself﹣control.They'remainlylittlebagsofsugar. Ifyoulovewholefruitthere'slittleevidencetoshow10eatingit一evenawholelotofit﹣isbadforyourhealth.
VolunteersarevitallyimportantforMelbourne'stourism.TheyprovideinformationonMelbourneforaroundtwomillionvisitorseachyear.TheirloveandknowledgeofthecityaddtoMelbourne'sreputationasafriendlywelcomingandculturallyvibrantcity.Ifyouwouldliketoreceiveanemailadvisingyouonthenextrecruitment招募sessionpleaseemailtourism@melbourne.vic.gov.au.TheCityofMelbourne'stourismbranchgenerallyconductstwovolunteerrecruitmentintakeseachyearforthefollowingtourismprograms*CityAmbassadors*MelbourneVisitorBoothatBourkeStreetMall*MelbourneVisitorCentreatFederationSquare*MelbourneGreeterServicePlacesarelimitedandpotentialvolunteersmustparticipateinaselectionprocessbasedonthefollowingcriteria.Volunteersmustbe*passionateaboutMelbourne*customerservicefocused*familiarwithcomputer*availableforonefour﹣hourshift轮班eithermorningorafternooneveryfortnightforaminimumofoneyear*teamplayerswholovemeetingpeople*abletodemonstrateacommitmenttotheCityofMelbourne'svaluesMoreinformationTofindoutmoreaboutbecomingavolunteercontactusonlineorphonetheCityofMelbourne'sVolunteerProjectOfficerTourismMelbourneon0396589658.ForothervolunteeringopportunitiesseenationalvolunteerrecruitmentwebsiteGoVolunteer.1WhichofthefollowingisNOToneofthequalificationstobeavolunteer?A.Beingwillingtocooperate.B.Havingcomputerskills.C.Beingabletodoshiftworkeverynightforayear.D.HavingpassionforMelbourne.2Howcanyougetothervolunteeringchances?A.Byemailingtourism@melbourne.vie.gov.au.B.Byseeingnationalvolunteerrecruitmentwebsite.C.ByphoningtheCityofMelbourne'sVolunteerProjectOfficer.D.BycontactingTourismMelbourneonline.3Whereisthetextmostprobablytakenfrom?A.Agovernmentwebsite.B.Aradioreport.C.Abookreview.D.Ageographytextbook.4Whatmaybethebesttitleforthetext?A.GuidetoTouringinMelbourneB.WelcometotheCityofMelbourne!C.DoesVolunteeringPayBack?D.TourismVolunteerProgram!
Pictureaniceberg冰山.You'llprobablyimaginesomethingwhiteassnowrisingupoutofabluesea.Buticebergscanbeallsortsofshades.Theycanbefromafrostybluetoanattractivegreen. Researchersandsailorshaveobservedemerald翠绿色icebergsforyears.Alargepieceoficemast﹣highandgreenasemeraldevenappearsinSamuelTaylorColeridge's1834poem.Buttheyhaven'tfoundoutexactlywhytheseicebergslookthewaytheydo. AnewpaperledbyStephenWarrenwaspublished.Itallhastodowithwhaticebergsaremadeoutof.Icebergsbreakoffglaciers冰川oriceshelveswhichhappensmainlyaroundAntarcticaandGreenland.Theybegintheirlivesassnowfallthataccumulatesovertime.So.icebergscontainairpocketswiththeformofbubblesthatspreadlight.Withsomeexceptionsandrarelinesglaciericetendstolookbluishwhite. AtfirstWarrenguessedthatthegreenwasaproductofmeltcarbon.Anditcamefromrottingplantsorseaanimals.Butsamples样本didn'tproveit.AnotherideastartedtotakeshapeaftertheyhadfoundahighconcentrationofironinasampleofseaicefromtheAmeryIceShelf. Whenglaciersrubacrosslandtheyproducewhat'sknownasglacierflour.Itisaproductofbedrockbeinggroundclownbythemovingmass.Asglaciersmoveawaytheseremainsareusuallywashedoutintowater.inparticlessometimestoosmalltobenoticeabletoyoureyes.Butonland.soilandrockscontainironoxidesthatoftenhaverosycolors.likeredsyellowsandbrowns﹣andsincetheseaicecontained500timesmoreironthantheglaciericeWarrenwonderedwhethertheremainswereresponsibleforicebergstakingonagreenappearance. Hedoesn'tknowforsure.He'shopingtosecuremoneysothathecanreturntotheareaandstudytheicebergsthemselves. 1WhyisSamuelTaylorColeridge'spoemmentionedinthetext? A.Ittellswhyicebergslookthewaytheydo. B.Itdescribesvividlywhaticebergsarelike. C.Itsayscausesoftheappearanceoficebergs. D.Itprovestheexistenceofcolorfulicebergs. 2WhatcanweknowaboutStephenWarren'spaper? A.Itdrawsonresearchers'andsailors'views. B.Itistherecordofthemovementoficebergs. C.Ittalksabouthowicebergscomeintobeing. D.Itisacollectionofvarioussocialphenomena. 3Whatdoestheunderlinedworditinparagraph4referto? A.Asampleofseaice. B.Warren'sfirstguess. C.Warren'sideaoniron. D.Aproductofmeltcarbon. 4Whatisparagraph5mainlyabout? A.Thepossiblereasonwhyicebergslookgreen. B.Wheremostoficebergseventuallydisappear. C.Howicebergstakeinthecolorsfromglaciers. D.Thewayinwhichicebergsbreaksoffglaciers.
2019年的元宵月不仅恰逢“年度最大最圆月”还是“十五月亮十五圆”最圆时刻出现在19日23时54分．月球过近地点的距离只有35.68万千米是月球全年距离地球最近的一刻此时月亮直径最大把数据35.68万千米用科学记数法表示为千米．
假定你是李华你校将迎接英国学生代表团.作为学校书法社团部长请你写一篇发言稿要点如下 1.介绍书法用品 2.阐述书法学习的好处 3.邀请英国学生参加书法练习活动 注意 1.词数100左右 2.可以适当增加细节以使行文连贯 3.开头已为你写好. 参考词汇书法calligraphy 文房四宝theFourTreasuresoftheStudywritingbrushinkstickpaperinkslab Dearfriends We'dliketoshareourculturewithyoubyintroducingyoutotheartofChinesecalligraphy.
阅读材料求1+2+22+23+24+…+210的值． 解设S＝1+2+22+23+24+…+210① 将等式两边同时乘2得2S＝2+22+23+24+…+210+211② ②﹣①得2S﹣S＝211﹣1即S＝﹣1． 请你仿照此法计算 1求1+3+32+33+34+…+32019的值 2观察归纳上述过程并直接写出下列式子的结果a+aq+aq2+aq3+aq4+aq5+…aqn＝并证明．
如图在四边形ABCD中AB∥CD∠ABC＝∠ADCDE⊥AC垂足为E．DC＝7连接BE． 1求证四边形ABCD是平行四边形 2若△ADE的面积为∠DAC＝60°求四边形ABCD的周长．
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. 删除把多余的词用斜线\划掉. 修改在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改仅限一词. 2.只允许修改10处多者从第11处起不计分. MylittlebrotherandIwentshoppinginnewlyopenedsupermarketinourcitylastMonday.Wetastedalittledeliciouscheesebiscuitsandbuythreeboxesofcandies.SeenoneofmyfavouritechocolatecakesIquickenedmystepsthroughthecrowd.AfewminuteslateIcouldn'tfindmybrotherandgotanxious.Sincethereweresomanypeopleinthesupermarketsoitwasquitetoughformetofindher.Ihadtoaskasalesmanforsomeadvices.Itwasn'tlongafterthesalesmanfoundaloudspeakerandstartedtosearchformybrother.ThanksforthesalesmanImanagedtofindmybrotheratlast.
HalloweenComingOut Amanwasshotinthefaceduringabankrobbery.Thatwasthenewsaboutmefiveyearsago.FromthenonIneverlookedina1itevenscaredmyselfwhenseeingmydestroyedface.Ilivedinmyhousealonewithoutoutsidecontact.ButonenightIwasmakingan2.ItwasHalloween. Whatafittingnightformeto3!Ilongedforhumancontact.WhenmypumpkinlanternsmiledatoothywelcomeinmyfrontdoorIheardfootstepsandgiggling咯咯的笑aschildrencameclosetomyhouse. Trickortreattheycried. Myhandsstartedto4.Iopenedthedoorandgavethema5smilethroughmydamagedlipsbeneatharoughscarwheremynoseonce6. Doyouwantatrickordoyouwantatreat?Myvoicesoundedmorelikeaghost.The7expressiononthechildren'sfacessuggestedeverything. Treat!They8pickedacandyortwofrommybucketandrantothe9oftheirparents. Iclosedthedoorandpressedmybackagainstit.IfeltdizzybutI10it.Thenthebellrang.Trickortreat.a11voicecametome.IopenedthedoortofindasmallgirlwearingaShirleyTemplemask. HiShirley.Ispokequietlynotto12her.Aren'tyoubeautifultonight? ShestaredatherfeetandshookherheadNo. Yesyouare.You'reShirleyTemplethemostbeautifulgirlintheworld. Shelookedupatmeandpulledher13totheside.Seeingherdeformed变形的facemyheartmissedabeat. WellIthinkyouarebeautifuldarling.Isaidgently. Atthewordshereyesconnectedwithmine.Anuncertainhandreachedtowardmybucketandtookonepieceofcandy.Thankyou.Hervoicewasa14.Sheturnedandrantohermother.Inoddedmyheadtohermotherandgavethembotha15. Iclosedmydoorandturnedoffmygatelamp.My16lifebeganagain. ThenextmorningIheardmydoorbellring.Itriedtoignoreit17itrangagain.IwenttothedoorandcalledoutWho'sthere? It'sShirleyTempleandherMom. Iopenedthedoorinafew18andlooked.Itwasthewomanandherdaughterwithouthermask.BeforeIspokethemothersaidMygirlsaidshewantedtomeetyou.Iwatchedtearsstartto19inthemother'seyes.Thisisherfirsttimeoutsidewithouthermask. Ipulledthedooropenandthatwasalsothefirsttimeinfiveyearsformetoinvitesomeoneintomy20. 1A.mirror B.wallet C.pocket D.bank 2A.expectation B.appointment C.introduction D.exception 3A.act B.stay C.appear D.flee 4A.shake B.cross C.dance D.tap 5A.bitter B.friendly C.simple D.quiet 6A.lived B.sat C.breathed D.slept 7A.moved B.excited C.shocked D.puzzled 8A.easily B.politely C.sadly D.quickly 9A.security B.shadow C.defense D.sight 10A.finished B.promoted C.got D.did 11A.thin B.loud C.claim D.clear 12A.interrupt B.scare C.discourage D.cheat 13A.gloves B.hat C.mask D.glasses 14A.whistle B.whisper C.signal D.sigh 15A.glance B.wave C.hand D.surprise 16A.busy B.social C.meaningful D.lonely 17A.for B.so C.but D.or 18A.seconds B.efforts C.inches D.steps 19A.well B.dry C.freeze D.fix 20A.future B.story C.mind D.life.
DutchdesignerDaanRoosegaardehasspentmuchofhistimeseekingartisticsolutions解决方案tosolveourenvironmentalproblems.HispastprojectsincludeBioluminescent生物发光TreestolightstreetsaSmog﹣FreeTowertocleanBeijing'spollutedair.andGatesofLight.whichusestheheadlampsofpassingcarstolightupthe60floodgatesoftheAfsluitdijkamajordamintheNetherlands.Nowheishopingtousehisskillstosolveapressingglobalproblem﹣spacejunk! Scientistsguessthatthereareover500000bitsoflargerubbish.TodealwiththeproblemRoosegaardeintendstoachievehisgoalbyeducatingthepublicabouttheneedofthesituationandcomingupwithpossiblesolutions.Theplan.calledtheSpaceWasteLab.startedinOctober2018withalaser激光showintheNetherlands.TheuniqueoutdoorartworkofLEDsusedreal﹣timetrackinginformationtopointatpiecesofspacejunkfloatingataltitudesof200to20000kilometers.Theexperiencewasdesignedtomakethepublicknowmoreabouthowmuchspacejunkthereare. Tofindasolutionthedesignerhasbeenthinkingwithexperts.OneoftheprojectsbeingconsideredisShootingStarswhichattemptstoreintroducethetrashtotheatmosphereinacontrolledway.Uponreentry.thewastewouldburnintheatmospherelikeashootingstar.Roosegaardeenvisagesthatifsuccessful.burningspacetrashcouldsomedayreplacefireworksatlargepublicevents! InSeptember2018.theRemoveDEBRISsatellitesuccessfullysentanettocatchatargetwhileorbitingatanaltitudeofabout300kilometers190miles.Sometimethisyear.thecapsulewillsetfreeaharpoonthathasbeendesignedtoremovespacetrash.AttheendofitstaskRemoveDEBRISwillletgoasailtobringthesatelliteitself.and.hopefullysometrashbackintotheatmosphere.whereitwillburnup. 1WhatcanweinferaboutDaanRoosegaarde? A.Heistooaggressivetoputforwardgoodplans. B.Heiscreativeinsolvingenvironmentalproblems. C.Heisfondofspendingallofhistimeseekingartskills. D.Heissensitivetoartreflectedinenvironmentalprojects. 2WhywasalasershowheldinOctober2018? A.Toconfirmreal﹣timeinformationaboutspacetrash. B.ToshowthegreatbeautyofLEDtocommonpeople. C.Toraisepublicawarenessoftheamountofspacetrash. D.Toinspirepeopletoconsiderthesolutiontospacetrash. 3Whatdoestheunderlinedwordenvisageinparagraph3probablymean? A.Suspect. B.Demand. C.Advise. D.Imagine. 4Whatisthefunctionofasail? A.Bringingthesatellitetoatmospheretoburn. B.Keepingtrashtravelingalongitsownorbit. C.Takingthesatelliteawayfromatmosphere. D.Removingspacetrashoutofthecapsule.
AfewyearsagomywifeandItookatriptoCostaRica.Uponarrivalwe1acarandheadedouttoourfirstdestinationwhichwasafewhoursaway.Ihada2soIfiguredI'dbeingreatcondition.About20minutesintothedriveIfoundmyselfpractically3intheunmarkedstreetsanddirtyroads.Upset.IturnedtoSiriavirtual虚拟的assistantinmyphoneforhelp. Itypedthe4toourdestinationinmyphoneandinstantlySirihad5thebestroute路线togetthereandwewereonourway. Theonly6wasthatthingsdidn'talwaysgothewayIthoughttheywould.Withthestreetsnotbeingwell7Iwouldsometimesmissaturnandheadinthe8direction.LuckilySirinevergot9withme.AnytimeImissedaturnSiriwouldsimply10andsayRecalculatingroute.11route.AndwithinafewsecondsSiriwouldhaveanewroute12togetustoourdestination. SometimesthenewroutemeantIhadto13totherightturnandsometimesshefoundadifferentroutethattookmynewlocationinto14Eventuallywemadeittoourhotel15andenjoyedsomebeautifulsceneryalongtheway. Mostpeoplemakethe16ofthinkingthatsuccessandhappinesscomefromsomeonesettingagoalandthen17straighttowardsit.The18isthatthereisnostraightpathtosuccess.Thereisn'teventhe19path.Therearemanypathsthatcangetyoutoyourgoals.Youjusthavetobe20torecalculateyourroutewhenyoumissaturnorthereissomethinginyourway. 1A.produced B.repaired C.rented D.purchased 2A.car B.phone C.compass D.map 3A.absorbed B.lost C.experienced D.free 4A.address B.approach C.receipt D.schedule 5A.polished B.discovered C.opened D.managed 6A.fear B.difference C.sympathy D.problem 7A.marked B.paved C.arranged D.expanded 8A.illegal B.new C.wrong D.potential 9A.generous B.mad C.concerned D.cautious 10A.breakdown B.cutin C.getup D.goaway 11AAbandoning B.Cancelling C.Reaching D.Changing 12A.checked B.updated C.adjusted D.planned 13A.point B.lead C.return D.apply 14A.order B.direction C.account D.place 15A.safely B.frequently C.hungrily D.gradually 16A.mistake B.excuse C.accident D.trouble 17A.accumulating B.withdrawing C.marching D.fleeing 18A.answer B.truth C.condition D.privilege 19A.first B.suitable C.accurate D.only 20A.willing B.proud C.anxious D.ambitious
某校计划修建一个既是轴对称图形又是中心对称图形的花坛从学生中征集到设计方案有等腰三角形正五边形正六边形平行四边形菱形矩形圆等图案你认为符合条件的有几种
ThePalaceMuseumiscelebratingitsupcoming600thanniversary.Itsnewattempt1fillyoungergenerationswithcultureisafabulousmixofcelebritiesancienthistoryandmoderntechnology.ThePalaceMuseumishometo2rough1.86millionprecioushistoricalrelics遗迹andamong3theNorthSongDynastymasterpieceAlongtheRiverduringtheQingmingFestivalpaintedbyZhangZeduan4considertobeofgreatvalue.ThepaintinghassuchareputationofbeingChina'sMonaLisa5millionsofvisitorsareattractedtoenjoyit.The6originmasterpieceisstatic静态的anditseemsthatthegeneralpublicrarelyknows7thepaintingisattemptingtoconvey.Since2000thePalaceMuseum8cooperatewithtechnologycompaniestomakethesesilenthistoricalrelicscomealive.Thedigitalizedversionoftheworkcanbeshownonthegiantscreeninanexhibitionroom.Visitors9wearVRglasseswilltakeaboatandexploretheneighborhoodoftheBianRiver.Thankstomoderntechnologyalltheprecioushistoricalrelicswillbebrought10lifewiththeirobscure晦涩的wordseasiertounderstand.
如图是由5个相同的小正方体组成的立体图形这个立体图形的左视图是
Helpfultipsforcollege﹣boundseniors Researchingacollegeisoneofthemosttime﹣consumingtasksthatyou'llencounter.1Forexamplewhatclassesandfacilitiesthecollegehastoofferandwhatsportsitoffers.Afternarrowingyourchoicestoagroupofcollegesyou'llhavetostarttoresearchtheseindepth.2Heorshemaybeabletohelpyoufindthingsaboutthecollegesthatyoucouldnotgetyourself. Knowingwhatyouwanttostudyisanotherkeytolookingforacollege.3ByknowingwhatIwanttodoIcanthenlookatcollegesthatI'vebeenthinkingaboutapplyingtoandnarrowmychoicesdown.Ifacollegedoesn'thavethecoursesIneedthenit'sdefinitelyoutofthepicture. Anotherkeythingtolookforisthecollege'stestingrequirements.4SomecollegesalsorequireanSATIItestincertainareasforexampleEnglishorMath.Remembertolookatacollege'sGPArequirementstoo.Youmayfindacollegewherethere'severythingyouwantbutyourGPAisn'thighenoughtobeconsidered.Inthiscaseyoumayneedtoattendajuniorcollegeforoneortwoyears. 5Atthispointyoumaywanttohavealongdiscussionwithyourparentsandfindouthowmuchthey'rewillingandabletospendoncollege.Ifitisn'tenoughtocoveryourfulltuitionthenyoumaywanttoapplyforfinancialaidorascholarship.Andyourfinaloptionmaybelookingforacollegethatdoesn'tcostasmuch. A.AllcollegesrequireanSAToranACTtest. B.Andlastlybutdefinitelynottheleastistuition. C.Lookforacollegenowifyouplanonattendingone. D.Youneedtofindoutmanybasicsaboutpossiblecolleges. E.Ifyouwillbeaseniorinthenearfuturethisarticleisforyou. F.Iplantomajorinbusinessmanagementandminorincomputerapplications. G.Ifyouhaveacollegecounseloratyourschoolthiswouldbeagoodtimetoaskforadvice.
计算|﹣2019|＝．
ItwasdaysorevenweekssinceIhadbeenleftontheisland.MyonlycompanionwasadogcalledPhillywhichhadsurvivedtheshipwreck.Memoriesofwhathappenedwerestillfresh. Themagnificenceoftheshiphadgivenusallafalsesenseofsecurity.Asthefirstsignsofthestormstartedourcaptainannouncedit'snothingmuchjustanotherstorm.Yethewaswrong!Thestormhittheshipsobadlythatlargeholesweremadeatthesidesoftheship.Asthefreezingwaterstartedrushinginourshipwasconsumedquicklybythedarkwater. MytrainofthoughtwasdisturbedbyPhillylickingmyhanddearly.Areyouhungry?Ispokemyfirstwordseversincetheshipwreckoccurred.Woofwoof!BarkedPhillyenthusiastically.Atthismomentmystomachgavealoudgrowltoo.Icouldnotrememberwhenmylastmealwasprobablyaten﹣coursedinnerontheship.AsIhadneverfishedbeforeIthoughtmaybeIcouldtrysomethingsimplerlikepickingfruits.WithPhillyatmysidearmedwithasharpbranchwewalkedintotheforestontheislandtogether.SuddenlyIthoughtIheardnoises.Couldtherebeanyoneelseonthisisland?Iwondered.Aswewerelookingforfruittreeswechancedupononethatboreyellowjuicy﹣lookingfruit.Phillystartedbarking﹣wehadcompany.Itwasadark﹣skinnedwomanholdingasharpspeardressedinfurandgrass.Ibackedawayfromherafraidthatshewouldbeaggressive.ThenIsawthatshewastryingtosaveus.Pointingherspearatthefruittreesheshookherheadstrongly. InoddedathertoshowIunderstoodwhatshewassaying.SignalingtoustofollowhersheturnedtowalkalongasmallpaththatIhadnevernoticed.Attheendofthesmallpaththerewasasmallvillage.Tearsofjoyfilledmyeyes. 1Whathappenedtotheshipthewriterhadbeenon? A.Itwasfrozeninthesea. B.Itwasturnedoverbythestorm. C.Itwasdesertedbecauseitwasinsecure. D.Itsankduetothedamagecausedbythestorm. 2AccordingtothepassagewhichofthefollowingcanbestdescribePhilly? A.Activeandfriendly. B.Caringbutaggressive. C.Smartandfaithful. D.Noisybutenthusiastic. 3Whydidthewriterwalkintotheforest? A.Totakeshelterfromthestorm. B.Togotoasmallvillage. C.Tofindsomeoneforhelp. D.Tolookforsomethingtoeat. 4Thewomanmostprobablytriedtotellthewriterthat. A.thefruittreewasn'tthebestchoice B.thefruitwasunfitforeating C.thewriterwasn'tallowedtopickthefruit D.shewasn'tafraidofthewriter
如图AB是⊙O的直径且AB＝6．点C是⊙O上的一动点连接ACBC在AC的延长线上取一点D使得∠CBD＝∠DAB点G为DB的中点点E为BG的中点连接AE交BC于点F． 1试判断直线BD与⊙O的位置关系并说明理由 2当∠CGB＝60°时求的长 3当AE∥CG时连接GF若AF＝4求BD的长．
Screamifyouwanttochargeyourphone.ThankstothewondersofscienceridersonThorpePark'snewattractionarollercoaster过山车calledTheWalkingDeadcannowpowertheirsmartphonesbyscreamingloudly.That'sbecausetherearedevicesonitthat'harvestkineticenergy'动能.Theparkconductedresearchwhichshowsthatmillennials'biggestfearistheirphonesrunningoutofbatterysothedeviceshouldprovepopular.AlloftheWalkingDead'scarriageshavebeenfittedwiththeharvestingdeviceswhichnotonlyharvesttheenergyofscreamsbutthatfromg﹣forceandvibrations振动too.Theunitsarethenremovedfromthecarriagesbystaffanddepositedintoanon﹣sitemobilechargingpoint.ThorpeParksaid'Ifthrill﹣seekersarebraveenoughtoopentheireyestheywillseeasetofLEDlightsinbloodredpoweringupasguests'screamsbecomelouderthroughoutthespine﹣tingling90﹣secondexperience.'DesignedandinstalledbyresearchersatQueenMaryUniversityLondonandtheengineeringteamatThorpeParkResortthetechnologytookthreemonthstoimplement执行fromdesigntoinstallation.Itwillbeavailableatthethemeparkforaninitialtrialperiod.Ifthisprovessuccessfulthetechnologymaybecomeapermanentfixturefortheremainderofthe2018season.ThorpeParkResort'sJohnBurtonwhocameupwiththerideconceptsaid'TheWalkingDeadTheRideis15outof10onthescarefactorscale等级soitmakessensetobeabletocombineandusethepowerofourvisitors'screamsandtheride'svibrationstohelpsolveaproblemeachandeveryoneofusfaces﹣losingthechargeonourmobileswhenwe'reonadayout.'DrJoeBriscoeSchoolofEngineeringandMaterialsScienceatQueenMaryUniversityofLondonsaid'Thisisanexcitingconceptthatwillundoubtedlybeusedmorefrequentlyinthefuture.Thesystemusesaminienergyharvestertocapturethekineticenergytransferringittoaseparateelectricalcircuitandstorageunitwhichisenoughtochargeamobilephone.'1Wecanlearnfromthetextthat.A.aphoneshouldbeputintherollercoastertobechargedB.itwasJohnBurtonwhodesignedandinstalledthedeviceC.theenergyofscreamsg﹣forceandvibrationscanbeharvestedbythedeviceD.thetrialperiodofthetechnologywilllastthreemonths2Whatdoestheunderlinedword'spine﹣tingling'meaninParagraph4?A.Unforgettableandsatisfying.B.Interestingandinspiring.C.Exhaustingbutdelightful.D.Frighteningbutexciting.3WhatisDrJoeBriscoe'sattitudetowardthefutureofthenewconcept?A.Skeptical.B.Optimistic.C.Critical.D.Neutral.4What'sthemainideaofthetext?A.Thetraditionalwayofchargingyourphoneisonthewayout.B.Anewbatteryforpoweringyourphoneisinvented.C.Visitors'screaminThorpeParkcanbeusedtochargethephone.D.ThemosteffectivewayofchargingyourphonehasbeenfoundinThorpePark.
WhyYouShouldn'tPunishYourKidsForLyingIt'snoeasytasktostopyourchildrenlying.TherearemanyinfluencesTVmoviesvideogamesandsomegreatbooksinwhichliesarecommon.Childrenseeparentslietoothersonlytobepolite.MostparentsaddtothatwithtalesaboutthelivesandactivitiesofSantaClausortheToothFairytobringjoyortolessenfears.1butforsomechildrenlyingcanbecomeaproblem.Themostcommonreactionstochildrenwholieareexplainingwhyitiswrongandpunishingthem.2.Herearethreebettertoolssupportedbyresearchtouseinstead.PRAISEYoucouldaskyourchildtosaysomethingthathappenedatschoolthatistrue.Whenyourchildobeyspraisehimenthusiastically.Bespecific'Thatwasgreat!YoutoldmewhathappenedjustasIasked.Wow!'andgiveyourchildahugorahighfive.Aimforoneortwointeractions互动likethisaday.Ifyouhappento'catch'yourchildinaliesaysomethinglike'Thatisnottrueandcouldgetyouintroubleoutsideofthehome.'MODEL3.Thiscouldbeaboutsomethingthathappenedwhenyouwereachildorsomethingthathappenedduringtheday.Itneednotbedramatic.Anotheroptionistoplayagameatdinner.Eachpersontellsonethingthatwastruethatday.Againgivealittlepraisetothechildwhonormallyliesifheplaysalong.DECREASEPUNISHMENTANDMORALIZINGSomechildrenareunlikelytochangebehaviorordeveloptheconductyouwant.Thatdoesnotmeanyoucanignoretheirlyingorletitgo.Ratheruseverymildpunishmentlightscoldingshortlossofprivilegeabrieftime﹣out.4.Trytheseproceduresfortwotothreeweeksandseewhereyouare.Usuallyliescanbedroppedbythen.5butwiththerightencouragementcanbedramaticallylessened.A.ParentspunishchildrenbecausetheyareinapositionofgreaterpowerB.ButaswaysofchangingbehaviortheseareineffectiveC.TheythinkitunnecessaryforchildrentotellalieD.ParentsdothisoutofloveE.SeverepunishmentsarenotalwayseffectiveinactuallychangingthefrequencyoflyingF.YoushouldsetagoodexampletoyourkidsandexplicitlytellthetruthG.Itisunlikelythatlyingwillbecompletelyremoved
函数y＝中自变量x的取值范围是
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