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△ABC的内角A,B,C的对边分别为a,b,c,a=1,c=5,cos=,则b=( )
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高二上学期数学《》真题及答案
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设锐角三角形ABC的内角ABC的对边分别为abca=2bsinA1求B的大小2求cosA+sinC的
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△ABC的内角A.B.C.的对边分别为abc已知a=bcosC+csinB则B.=.
在△ABC中已知abc分别为△ABC内角ABC的对边.若b=a且sinB.+cosB.=0则A=.
△ABC的内角A.B.C.的对边分别为abc若abc成等差数列且2a=3c则cosB=
设△ABC的内角ABC的对边长分别为abcb2=ac求B.
△ABC的内角A.B.C.的对边分别为abc已知b=2B.=C.=则△ABC的面积为________
在锐角△ABC中内角A.B.C.的对边分别为abc且2asinB.=b.1求角A.的大小2若a=6b
△ABC的内角A.B.C.的对边分别为abc已知2cosC.·acosB.+bcosA.=c.1求C
△ABC的内角A.B.C.的对边分别为abc已知2cosC.acosB.+bcosA.=c.1求C.
△ABC的内角A.B.C.的对边分别为abc已知a=bcosC+csinB.1求B2若b=2求△AB
在锐角△ABC中内角A.B.C.的对边分别为abc且2asinB=b.求角A.的大小.
△ABC的内角
,
,
的对边分别为a,b,c,若c=2,b=6,B.=120°,则a=( ) A. 6B. 4 C. 3
2
在△ABC中内角A.B.C.的对边分别为abc已知a-b=2c=4sinA=2sinB.则△ABC的
在△ABC中内角A.B.C.的对边长分别为abc且2b-ccosA.=acosC.1求角A.的大小2
设△ABC的内角A.B.C.的对边分别为abc且则c=___________
在锐角△ABC中内角A.B.C.的对边分别为abc且2asinB.=b.求角A.的大小.
△ABC的内角A.BC的对边分别为abc若2bcosB=acosC+ccosA则B.=
设△ABC的内角A.B.C.的对边分别为abc已知cosA.-C.+cosB.=1a=2c求角C.的
△ABC在内角A.B.C.的对边分别为abc已知a=bcosC+csinBⅠ求B.Ⅱ若b=2求△AB
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Eco﹣ResortManagement Ecotourismisoftenregardedasaformofnature﹣basedtourismandhasbecomeanimportantalternativesourceoftourists.Inadditiontoprovidingthetraditionalresort﹣leisureproductithasbeenarguedthatecotourismresort度假村managementshouldhaveaparticularfocusonbest﹣practiceenvironmentalmanagement.CouranCoveResortissuchatouristattractionlocatedonSouthStradbrokeIslandAustralia. Sustainable可持续的PracticesofCouranCoveResort SouthStradbrokeIslandisseparatedfromthemainlandbytheBroadwaterwhichishometoawiderangeofplantcommunities.LocatedontheoffshoreislandtheResortisonlyaccessiblebymeansofwatertransportation.Itprovideshourlyferryservicefromtheharbouronthemainlandtoandfromtheisland.WithintheResorttransportmodesincludewalkingtrailsbicycletracksandthebeachtrain.Thereceptionareaisthecounteroftheshopwhichhasnotchangedin8yearsatleast.Theaccommodationisanoctagonal八角形的building.Thesearelargeroomsthatarecleanbuttheequipmentisoldandinsomecasesjustworking.Theceilingfanonlyworksathighspeedforexample.Bedsarehardbutclean.Thereisatelevisionaradioanoldairconditionerandasmallfridgeineachroom. Asanecotourism﹣basedresortmostoftheplanninganddevelopmentoftheattractionhasbeenconcentratedontheneedtoco﹣existwiththenaturalenvironmentofSouthStradbrokeIslandtoachievesustainabledevelopment. WaterandEnergyManagement Thereisgroundwateratthecentreoftheislandwhichhasamaximumheightof3metresabovesealevel.Thewatersupplyisrechargedbyrainfallandiscommonlyknownasanfreshwateraquifer含水层.CouranCoveIslandResortobtainsitswatersupplybytappingintothisaquiferandcollectingitthroughapipe.Inordertonarrowthewaterusesalllaundryactivitiesarecarriedoutonthemainland.TheResortusesLPGpowerstationratherthanafueloilstationforitsenergysupplysupplemented补充bywindpowerwhichhasreducedgreenhouseemissionsby70%.Hotwaterintheeco﹣cabinsandforsomeoftheResort'svehiclesissolar﹣powered.Waterefficientfittingsarealsoinstalledinshowersandtoilets.VisitorswhostayattheResortareencouragedtomonitortheirwaterandenergyusagebyanin﹣housetelevisionsystemandarerewardedwithprizessuchasafreereturntriptotheResortaccordinglyiftheirusagelevelislow. Evaluation InthreeyearsofoperationCouranCoveIslandResorthaswon23internationalandnationalawards.Ithaseffectivelyimplementedcontemporaryenvironmentalmanagementpractices.HowevertheResort‟sgrowthwilleventuallybelimitedbyitscarryingcapacityandquantitycontrolshouldbeincorporatedinthemanagementstrategyoftheResort. 1InordertoachievesustainabledevelopmenttheResort. A.cancelsthetransportationservice B.researchesintoplantcommunities C.provideshighqualityaccommodation D.operatesinharmonywithitsnaturalsurroundings 2WhatisappliedforheatingwateronCouranCoveIslandResort A.TheLPGpower. B.Thepetropower. C.Thesolarpower. D.Thewindpower. 3AccordingtothestudyinthefuturewhatshouldtheResortfocuson A.Increasingthesupplyoffreshwater. B.Meetingtheneedofinternationalguests. C.Improvingthetourismentertainmentprojects. D.LimitingthenumberofthegueststotheResort. 4FromthepassagewecanknowthatCouranCoveIslandResort. A.suffershugelossinnaturalresources B.achievessuccessineco﹣resortmanagement C.setsagoodexampleforprofit﹣makingbusiness D.raisesstandardsinguest﹣monitoringmanagement
Howtohelpawheelchairuserintoachair Ifyou'relookingaftersomeonewhousesawheelchairknowingthecorrectwaytoassisthiminDtoandoutofhischaircanbequiteimportant.1Soit'snecessarytounderstandhowtolendahandsafelybeforeyouattempttodoso. 1.Preparethechair. It'scrucialtoensurethatthechairisreadyforthepersontositinbeforeyoubegintomovehim.Nevertrytoadjustthechairwhenyou'realreadybearingaperson'sweight.Insteadensurethatthechairisintherightpositionbeforeyoustart.2 2.Liftsafely. Beforeyoucanhelpawheelchairuserintoachairyouneedtobeawareofseveralfactorsaswellasthecorrectwaytoliftthechairuser.Makesureyouknowhowheavyyourfriendorfamilymemberisandthatyou'restrongenoughtolifthimtositsafelyinthechair.3Yourclothingandfootwearisalsoimportant.Ensurethereisnothingyou'rewearingthatcouldcatchandthatyourshoesallowcompletestability. 3.4 Loweryourfriendorfamilymemberintothewheelchairslowlyandsteadilymakingsuretheyarefullyseatedinthechair.Iftheyareabletostandandlowerthemselvesintothechairstandbehinditandholdontothehandlestomakesureitdoesn'tmove.5Beforemovingthewheelchairaskthemtoplacetheirhandsintheirlapormoreimportantlyawayfromthewheelssothattheycanfeelcomfortable. Aboveallcheckthatthepersonyouareassistingiscalmandrelaxedandhappytoreceivehelp. A.Makethemcomfortable. B.Rememberloleavethewheelchairbehind. C.Youshouldheinanareawithnoobstaclesintheway. D.Makesureyoucanhaveafreetalkwiththewheelchairuser. E.Notknowingtherighttechniquescanresultininjurytothewheelchairuser. F.Oncetheyareseatedswingthefootrestsbackintoplacemindingtheirlegs. G.Mostimportantlymakesurethewheelchairbrakesareonandthatthechairistotallystable.
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PublicSpeaking Publicspeakingcanbedefinedastheactofmakingaspeechinfrontofagroupoflisteners. Thetypesofpublicspeakingaredeliberatelystructuredwiththreegeneralpurposestoinformtopersuadeandtoentertain.Aninformativespeechhasapurposetoinformorgiveknowledgetoitsaudience.1Forpersuasivespeechthespeakerwouldtrytochangethemindsetperceptionorbehavioroftheaudiencefortheirowngood.Thusthespeakerneedstolookforcommongroundwiththeaudienceandtrytorelatetowhattheymightagreeon.Thelasttypeisaceremonialspeech.Ittendstobelessformalandmorepersonalthantheothertypesofspeeches.Nomatterhowwellyouknowthepersonyouaregivingspeechabouttrynottosaybadthingsaboutthemevenifitismeanttobeajoke. 2Sparingsometimetopracticewillhelpbuildconfidenceandhelpdeterminehowlongthepresentationwilllast.Asidefromitknowingwhotheaudiencewillbeisquitenecessary.Trytogetasmuchinformationaspossibleregardingthisparticulararearelatedtotheaudience.Knowingthebattlefieldinadvancewillgivethespeakersahugeadvantage. Languageisthemainaspectaspeakerneedstopayattentiontowhilegivingaspeech.3Aspeakerneedstochoosetheirwordscarefullyandmakeitcleartotheaudiencewhattheymean.Oftenwhengivenaspeechtheaudiencelookuptothespeakertogivethemsomethingnewanduseful.4Languageanddeliveryalonewillnotbesufficientifthespeakerdoesnothavethebodylanguage.Themovementandgestureofaspeakeralsoaffecttheaudience.Whileclosingthespeechorpresentationspeakerscanrestatetheirmainpointsjusttoremindtheaudienceoftheimportantthingsthathavebeensaid.5 A.Itneedstobeusedclearly. B.Thesespeechesmarkspecialoccasions. C.Theimportantthingtowatchaboutisnottoputintoomuchinformation. D.Thekeyofperfectinganythingisthroughpracticeincludingpublicspeaking. E.Theycanalsoenditwithaspecialmessageandencouragetheaudiencetoaskquestions. F.Knowinghowpublicspeakingisdoneisakeypartinunderstandingtheimportanceofit. G.Thusthespeakerneedstoknowhowtodelivertheirspeechtofulfilltheaudience‟sexpectation.
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.每处错误及其修改均仅限一词2.只允许修改10处多者从第11处起不计分.ItwasattheGreenStorethatIfindabrokenrockingchairandputitinbackofmytruck.Theseatwassplitintotwofromfronttoback.Otherthanthatitwasinexcellentlycondition.IthoughtIshouldrepairitsothatbythefollowingdayitwouldbesogoodasanewone.BySundayafternoonthegluehadsetandaftertwocoatofbrightwhitepaintthechairwasofperfect.IwasexcitingbecauseIwasgoingtosurprisemywife.Wewerenewparenttoabeautifulbabyboy.Ournewbabylovedtoberockedbutwedidn5thaveaproperrockingchair.Thischairwasbeautifulandhiswifewasveryhappywithit.
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OilPaintingWorkshop Jan.72019 ForAges15andUp BeginnersWelcome!ExperienceNotRequired! Registration登记Deadline﹣﹣Dec.312018 ClassSchedule 930﹣1000amWelcomeandRegistration 1000﹣1200amPaintingSession 1200am﹣100pmLunch 100﹣300pmPaintingSession 300pmEvaluationandDeparture Instructor JudyMooreGistAlexanderCertifiedInstructorandRossCertifiedInstructorismakinggreateffortstogivepeopleofallagestheopportunitytoexperienceAlexander'sTheMagicofOilPaintingandBobRoss'sTheJoyofPainting.BothWilliamAlexanderandBobRossPBSTVhostshaveinspiredthousandsoffirst﹣timepainters.Thewet﹣on﹣wettechniquehaveencouragedpeopleofallagestopickupabrushandputtheirdreamsoncanvas油画布.Judywilldothesameandyouarewelcometotakeaclassandseeforyourself.Attheendofjustonesessionyouwillbeamazedatthebeautifulpaintingthatyoucreateinjustafewhours.Youwillbecomemoreawareofbeautifulcloudshapesandcoloursyouignoredbefore.Thereisnothingmoreinspiringthanseeingthebeautifulscenerythatyoupaintandotherswilltreasureforever. FormoreinformationaboutJudyMooreGistclickhere. Cost ﹩75.00/aperson.Pricesincludeallinstructorfeesmaterialsandlunch. IfyouwishtopaybycheckpleaseprinttheOilPaintJan.pdfprintableregistrationformandmailitinwithpaymenttoHolidayLake4HEducationalCenter12674﹣HCampRoadAppomattoxVA24522. Refund退款Policy FullRefundDec.312018 NonrefundableafterDec.312018 FormoreinformationcontactHeathernBenninghoveat232﹣268﹣6777orheathern@vt.edu. 1Toattendtheclasspeopleshould. A.provideapieceofpainting B.payforitbeforeJan.72019 C.learnsomethingabouttheinstructor D.registerforitnolaterthanDec.312018 2TheMagicofOilPaintingandTheJoyofPaintingaremostprobably. A.artworks B.TVartprograms C.paintingexhibitions D.face﹣to﹣facepaintingcourses 3Thetextmostprobablyappears. A.ontheInternet B.inanewspaper C.onanoticeboard D.inacompanybrochure
1Suzanwantstobeanactressshecanchoose. A.CourseA B.CourseB C.CourseD D.CourseE 2CourseCisfitforthestudentswhomight. A.dealwiththenumbers B.workwiththedisabled C.runabusinessorganization D.designandconstructbuildings 3IfDavidchoosesCourseFhemightbeastudentwiththecareerinterestin. A.advertising B.politics C.nursing D.management 4Wherecanweprobablyfindthepassage A.Inacityguidebook. B.Inasciencejournal. C.Onaschoolwebsite. D.Fromanewsreport.
Accordingtolegendayoungmanwhilewanderingthedesertcameacrossaspringofdeliciouscrystal﹣clearwater.The1wassosweethefilledhisleathercontainersohecouldbringsomebacktoatribalelderwhohadbeenhis2. Afterafour﹣dayjourneyhe3thewatertotheoldmanwhotookadeepdrinksmiledwarmlyand4hisstudentlavishly浪费地forthesweetwater.Theyoungmanreturnedtohiswitha5heart. Latertheteacherletanotherstudent6thewater.Hespatitoutsayingitwas7.Itapparentlyhadbecomestale不新鲜的becauseoftheold8container.Thestudent9histeacherMasterthewaterwas10.Whydidyou11tolikeitTheteacherrepliedYouonlytastedthewaterItastedthe12.Thewaterwassimplythecontainerforangetofloving﹣kindnessand13couldbesweeter.Ithinkweunderstandthislessonbestwhenwereceive14giftsoflovefromyoungchildren.Whetherit'sanuglyplateorabraceletthenaturalandproper15isappreciationandexpressed16becausewelovetheideawithinthegift. Gratitudedoesn'talwayscome17.Unfortunatelymostchildrenandmanyadults18onlythethinggivenratherthanthefeelingembodied被体现init.Weshouldremindourselvesand19ourchildrenaboutthebeautyandpurityoffeelingsandexpressionsofgratitude.20giftsfromtheheartarereallygiftsoftheheart. 1A.desert B.voice C.spring D.water 2A.master B.teacher C.relative D.friend 3A.took B.presented C.show D.delivered 4A.thanked B.nodded C.laughed D.joked 5A.light B.heavy C.happy D.broken 6A.throw B.pour C.taste D.bring 7A.tasty B.bitter C.hot D.awful 8A.leather B.rubber C.metal D.firm 9A.asked B.added C.challenged D.doubted 10A.fragrant B.delicious C.smelly D.bitter 11A.have B.pretend C.happen D.intend 12A.gift B.meaning C.feeling D.drink 13A.none B.everything C.seldom D.nothing 14A.innocent B.precious C.guilty D.priceless 15A.demand B.response C.comment D.problem 16A.thankfulness B.smile C.laughter D.praise 17A.firstly B.friendly C.immediately D.naturally 18A.ignore B.value C.stress D.forget 19A.tell B.bring C.teach D.send 20A.Asaresult B.Inaword C.Afterall D.Inthemeantime
PizzaisaprettycommontreatbutwherediditstartHerearethreethingsyouprobablydon'tknowaboutpizza. 1Pizza'sOriginsAreHalf﹣Baked. TheNeapolitansinItalyareproudofsayingtheyinventedpizzabutit'sprobablymoreaccuratetosaytheyperfectedit.Theideaofputtingtoppingsonaflatbreadandbakingitstartedinthe6thcenturyB.C.ButthepeopleofNapleswerethefirsttoputthetomatoonaflatbreadinthe16thcentury.Fromitsstartpizzawasthefoodforthepoorasitwascheapfillingandeasytoeatontherun.InItalianthewordpizzareferstoanythingthatismadeandthenpressedflat. 2PizzaMargheritaIsNotExactlyaSymbolofItaly. Itissaidthatonedayin1889alocalbakernamedRaffaeleEspositocreatedthreepizzasforQueenMargheritawhenshewasonatourofItaly.ThequeenlovedtheversionthathadthetomatobasilandmozzarellacheeseanditjusthappenedtomatchthecolorsoftheItalianflag.SoEspositonamedthepizzaafterher. ButScottWienerpointsoutthatItalywasunifiedinnameonlyin1889soitwasunlikelyanyNeapolitanbakerwouldwanttocelebratetheNorthernconquerorFurthertheletterofgratitudeforthepizzafromtheroyalhouseholdthatPizzeriaBrandidisplaysappearstobeafakeandmayjusthavebeenamarketingstrategy. 3HawaiianPizzaInventedbyaCanadian. SamPanopoulosfromGreeceoriginallymovedtoCanadaattheageof20.In1962hedecidedtoputsomehamandpineappleonapizzaatoneofhisrestaurantsinOntario. WejustdiditforfuntoseehowitwasgoingtotastehetoldtheBBCin2017.PanopoulosnamedittheHawaiianpizzaafterthebrandofthecannedpineappleheused.Themixtureofsweetandsavorytoppingsbecamepopularwithacertainpartofthepizza﹣lovingpublic.Theinventordiedin2017. 1Whowaspizzafirstmadefor A.Peoplewhowereverybusy. B.Peoplewhowererunningaway. C.Thepoorpeoplewhocouldaffordit. D.Soldiers. 2WhatisPizzeriaBrandi'spurposeofdisplayingtheletter A.ToshowhonorforQueenMargherita. B.Tohatchamarketingplot. C.Toprovethepizza'srelationwiththeroyalfamily. D.TotelltheworldPizzaMargheritaisexactlyasymbolofItaly. 3ThenameoftheHawaiianpizzacamefrom. A.anotherbrandoffood B.aCanadianrestaurant C.thefounder'sowninterest D.itsuniqueHawaiianflavor
RunningforaDream IwillneverforgetthatNovemberday.Itwashotterthannormal.Thiswasthe1myfatherandIhadwaitedsolongforbecausewehadbeenworkingtowardsthisraceforthreeyears.Dozensoffamiliarfacesfromchurchandschoolflashedacrossmyview.Theyhadcome2me.Isawworryand3onmyfather'sface.Thentheracebegan! ForthefirsttwoandahalfmilesIfelt4.Ihadneverbeforebeensoreadyforsomething.Theweeksleadinguptotheracewerefilledwithcontrolled5andastrictdiet.Myfriendshadn'tseenmeinweeksbuttheyunderstoodthe6requiredtomakemydreamareality.AsinallofmyracesIdidn't7outinthefrontIlovedthepleasureofpassingpeopleasmystrengthovertooktheirprematurespeed. Thenwithoutwarningmystrengthbegantodecrease.NeckandneckwithoneofmygreatestcompetitorsI8seethefinishline.Ihadbegunthefinaldashinto9whenmykneesbecameweakandmylegsgaveway.NothingIcoulddowouldmakethem10weight. Iwatchedasrunnersrushedbyme.11IknewmydreamsofvictoryweredestroyedIhadtofinishtherace.Howevermylegshurtbadly.Withallofthe12leftinmeIgotonmyhandsandkneesandcrawled爬inchbyinchacrossthefinishline.Voicesboth13andfamiliarcheeredmeon.Theygavemethecouragetokeep14untiltheveryend. Thedoctorswerethereinsecondsbutmyeyessearchedthecrowdforhim.TherewasonlyonepersonIwantedto15to.IwhisperedI'msosorryDadI'msosorryI16you.HelookedatmesayingYoucouldneverdisappointme.Sometimesthesethingsjust17.Allthatmattersisthatyoudidyourbest. Butweworkedso18.WhataboutourdreamHereachedoverformyhandandsaidDon'tyouknowthatyouaremydreamandithascometrue Itwasn'tlongbeforemyrunningshoeswerebackonmarkinga19pathformyjourneyIlearnedthatallofthemilesthetearsthesweatandthepainmydadandIexperiencedtogetherwerenotfora20.WhatIrealizedthoughwasthattohimIwasthegreatestprizehehadeverwon. 1A.dream B.weather C.result D.day 2A.for B.to C.across D.over 3A.coldness B.astonishment C.excitement D.amusement 4A.proud B.great C.nervous D.afraid 5A.programs B.studies C.instructions D.practices 6A.understood B.blamed C.criticized D.concerned 7A.look B.move C.start D.come 8A.should B.could C.must D.need 9A.relief B.spirit C.pleasure D.glory 10A.give B.feel C.hold D.add 11A.Where B.Because C.If D.Although 12A.trust B.emotion C.strength D.confidence 13A.loud B.foreign C.rough D.firm 14A.going B.running C.fighting D.training 15A.refer B.talk C.listen D.agree 16A.frightened B.disturbed C.disappointed D.bored 17A.develop B.change C.follow D.happen 18A.late B.hard C.closely D.quickly 19A.new B.near C.rough D.narrow 20A.wish B.duty C.rank D.race
假定你是李华近期你市的人民剧院将上演著名京剧霸王别姬FarewellMyConcubine你恰好有两张票.请给在你市学习汉语的美国好友Jeremy写封邮件邀他一同前往观看. 内容包括1.演出时间地点 2.演出内容 注意1.词数100左右 2.可以适当增加细节以使行文连贯.
A OnceIwasplayinginthewoodswhentheskystartedtoturndarkandthewindstartedtoblow.Isawabigblackcloud1movetowardsme.SuddenlyIfelttherainhittingmyface!Actuallyitwaspouring!ThenIsawlightninginthesky.AndlaterBOOM!!!Aloudclapofthunder!ThenIsawalittleoldhutandraninside.Itsmelledawfulandthewallswereshakingbutitwas2goodthannothing!Outsidethewindwashowlingandthingswereflyingaround.Ijuststoodinthecornercoldandscared.3luckymydadcameandfoundme.Iwassafe! B LiBaiwasaChinesepoetpraisedfromhisowndaytothepresentasaromanticfigure4tooktraditionalpoeticformstonewheights.Thirty﹣fourofhispoemsareincludedinThreeHundredTangPoems.5heearlypoetrytookplaceinthegoldenageofTangdynasty.ThisallchangedsuddenlywhenallofnorthernChina6destroybywar.Fortunatelymanyofhispoems7surviveeversinceenjoyinglastingpopularityinChinaandelsewhere. C TheChineseLunar月球ExplorationProgramisdesignedtobeconductedinthreestagesThefirstissimplyreachinglunarorbit轨道atask8completebyChang'e1in2007andChang'e2in2010.Thesecondis9landontheMoonasChang'e3didin2013andChang'e4in2019.ThethirdoneiscollectinglunarsamplesandsendingthemtoEarthataskforthefutureChang'e5andChang'e6missions.It10beChina'sfirstsamplereturnmissioninDecember2019.
若抛物线x2=2pyp>0在点12处的切线也与圆x2+y2﹣2x+2y+2﹣a=0相切则实数a的值为.
FreeEntrytoPalaceofVersailles﹣Save﹩18! ThePalaceofVersaillesisoneofthelargestandmostsplendidcastlesintheworld.Havingaround2143windows1252fireplacesand67staircasesthecastleisoneofthemostvisitedattractionsinFrance. Asafineexampleof18th﹣eenturyFrenchartthishistoricbuilding‘hasbeenonUNESCO'sWorldHeritage遗产Listfor30years. AtfirstitjustuhuntinghousebuiltbyLouisVIII.ButLouisXIVchosethesitetobuildthepalaceweknowtodaythesymbolofroyalabsolutism专权专治andclassicalseatofpowerin1789butgotroleinthe19thcenturyastheMuseumoftheHistoryofFrancewhichwasfoundedwhenLouisPhilippebecamethekingin1830. Thishistoriccastlewithitsbeautifularchitectureandgardensandlonghistoryisa.must﹣visitsightonasightseeingtriptoParis. ◆OpeningTimes HighseasonIApril~31OctobereverydayexceptMondays900~1830.Lastadmission1800. LowseasonNovember~31MarcheverydayexceptMondays900~1730.Lastadmission1700. ◆EntrytothePalace TogettothePalaceofVersaillesbyRERCrailline大区快铁C线makesuretobuyaParis﹣VersaillesRiverGaucheticketzones1~4. WithaParispassyoucanvisitthepalacefreeofcharge﹣that'sasavingofEuros.PleasenotethatVersaillesisoutsidezone3butsingleRERtraintickettoVersaillescostyouonly﹩3.25. WithaParispassyoudon'tneedtoqueueupbutcanuseprivilegedPassholderentryagreatbenefitifyouarevisitingduringthebusyspringorsummerseasons. ◆NoteYourentrydoesnotincludethemusicalfountainshows.Whenthewatershowsaretakingplaceyouwillbeunabletovisitthegardensunlessyoupurchaseaseparateticket. 1WhatcanwelearnaboutthePalaceofVersailles A.Itwasusedasamuseumatfirst. B.ItwasbuiltinmemoryofLouisXIV. C.Itwastheofficialseatofpowerin1830. D.ItisnotsobusyinNovemberasinOctober. 2IfavisitorwantstoenjoythePalaceofVersailleshewill. A.reachzone3ontime B.beallowedtovisititonMondays C.spendsomemoneytakingtheRERtrain D.alsowaitinthequeuelikeothertravelers 3Inordertowatchthewatershowsyouhavetobuy A.aParisPass B.aticketspeciallyforit C.asingleRERtrainticket D.aParisVersaillesRiverGaucheticket
已知向量若则=.
Dujiangyanistheoldestman﹣madewatersystemintheworldand1wonderinthedevelopmentofChinesescience.Builtover2200yearsagoin2isnowSichuanProvinceinSouthwestChinathis3amazewatersystemisstilluesedtoday. InancienttimestheregioninwhichDujiangyannowstands4sufferfromregularfloodscausedbytheoverflowforthewaterfromtheMinjiangRiver.5helpthevictimsofthefloodingLiBingtheregiongovernortogetherwithhissondecidedtofinda6solve.LidesignedaseriesofchannelsbuiltatdifferentlevelsalongMountYuleithatwouldtakeawaythefloodwaterwhileleavingtheriverflowingnaturally.7goodstilltheextrawatercouldbedirectedtothedryChengduPlainmakingitsuitableforfarming. Oncethesystemwasfinishednomorefloodsoccurredandthepeoplewereabletolivepeacefully.TodayDujiangyanisadmiredbyscientistsfromaroundtheworldbecauseofonefeature.Unlikemoderndams8thewaterisblockedbyahugewallDujiangyanstillletswaterflowthroughtheMinjiangRivernaturally9enabletheecosystemsandfishpopulationstoexist10harmony.
在三棱锥P﹣ABC中PA⊥平面ABC∠BAC=120°AP=M是线段BC上一动点线段PM长度最小值为则三棱锥P﹣ABC的外接球的表面积是
双曲线的一个焦点为F过点F作双曲线C的渐近线的垂线垂足为A且交y轴于B若A为BF的中点则双曲线的离心率为
如图在四棱锥P﹣ABCD中底面ABCD为直角梯形AB∥CDAB⊥AD△PAB与△PAD均为等边三角形点E为CD的中点. 1证明平面PAE⊥平面ABCD 2若点F在线段PC上且CF=2PF求三棱锥F﹣BEC的体积.
假设你是红星中学高三学生李华.请根据以下四幅图的先后顺序写一篇英文周记记述你们上周邀请京剧名家来你校参与京剧进校园主题活动的全过程. 注意词数不少于60. 提示词京剧Beijingopera脸谱facialmakeup
在△ABC中角ABC所对的边分别为abc且. 1证明acb成等比数列 2若c=3且sin2C=2cos2C+1求△ABC的周长
WhenIwasfiveyearsoldmymothersufferedfromdepression﹣andotherhealthissuesleavingmetocareforher.This1reversedourrolesaschildandcaretaker. WhileIknewmymotherwassickI2thateverythingwouldbeokay.3in1997everythingwenthorribly4andmylifechangedforever. Adoptionisan5wordtoafive﹣year﹣oldbutwhenI6thatmymotherhadsignedmeovertostrangersIfeltitwastheultimatebetrayal.Isufferedfromshock7andconfusionasIattemptedto8mynewfamily.IdidlearntolovemynewparentsthoughIcouldn'tforgivemymotherfor9me.Hearingpeopletellmethatshediditinmybestinterest﹣thatsheactually10me﹣mademebitter.Iinsistedthat11shehadtrullylovedmsshewouldhavemadeitworkforourlittlefamily. HowevertheolderIgotthemoreIbegantounderstandhow12oursituationhadbeen.Wehadbeen13boxesofnoodlesandweevenlivedinourcar.Ihavestartedtounderstandthe14sheputmeupforadoptionandthatshereallydidsaveme. OnlyrecentlyhaveIbegunto15howamothercouldgiveherchildtostrangersandIrealizenowwhatasacrificeitmusthavebeenforhertoletmego.Shewas16buteveninherstatesheunderstoodthatshewaspullingmedownwithher.Shelovedme17anythingsoshewantedmetohaveachanceinlifeonesherealisedshecouldnolonger18me.WhenIlookbacknowIam19toher.EventhoughIresented怨恨herforalongtimeInowknowmylifehasbeenaspecilagiftonlybecauseshewas20enoughtogivemeup. 1A.trend B.direction C.situation D.operation 2Arecognized B.believed Cadmitted D.explained 3A.However B.Therefore C.Otherwise D.Besides 4A.well B.wrong C.mad D.common 5A.exact B.right C.warm D.foreign 6A.regretted B.wondered C.realized D.expected 7A.cold B.hunger C.tiredness D.anger 8A.giveup B.worryabout C.adjustto D.searchfor 9A.rejecting B.raising C.criticizing D.accompanying 10A.blamed B.loved Cfeared D.forgot 11A.although B.if C.since D.unless 12A.familiar B.simple C.desperate D.stable 13A.throwingaway B.chargingfor C.dreamingof D.survivingon 14A.reasons B.risks C.rules D.results 15A.remember B.understand C.ignore D.describe 16A.upset B.sick C.polite D.calm 17A.otherthan B.ratherthan C.morethan D.lessthan 18A.lend B.control C.teach D.offer 19A.grateful B.similar C.equal D.rude 20A.curious B.patient C.selfless D.careful
已知函数fx=|x﹣3|. 1若ft+f2t<9求t的取值范围 2若存在x∈[24]使得f2x+|x+a|≤3成立求a的取值范围.
ThereisarestaurantinmyMainetownthathasdonelittletoupdateitselfoverthepast80years.Thisispartofitscharmasisthewoodenphonebooththatsitsneglectedintheageofthecellphone.Ahthephonebooth.Weneeditnowmorethanever. Formeitsymbolizesthatphonecallswereonceprivateaffairseveniftheinformationbeingsharedwasnotsensitiveinanyway.Itwassimplyassumedthataphonecenversationwasmeantfortwopeopleandtwopeopleonly. Growingupinthe1960swehadonlyphoneinthehouse.AsakidIdidn'tgetormakemanycallsbecauseallmyfriendsfivewithinearshotandIcouldjustyelloutthewindowifIwantedtheirattention.IdohoweverrememberansweringthephoneaskingfortheidentityofthecallerandthenhandingthephonetomymomShe'dtakeitsayHelloMrs…onemomentpleaseandthenassheplacedherhandoverthereceiversheturnedtomeanddirectedThisisforme.Whydon'tyougooutsideandplay Flashforwardtowhatcellphoneshavedonetoourlife.Withinthespaceofafewyearsoverhearingprivateconversationsseemstobenormal.NotlongagoIwassittinginBoston'sSouthStationnearamanwhowasonhiscellphonewaitingformytrain. ThefollowingiswhatthemanhadtosayYesthat'sright.Theredandyellowroses.Thenhecontinuedtorecitehiscardnumberaridexpirationdate有效期.Istaredatthefellow.HeglancedatmeandaskedWhatMyresponsewasimmediateIrecitedhiscardnumberbacktohimalongwiththeexpirationdate. Thereisnolongerasenseofpersonalbordersorlimits.Thecellphonehasbecomeamegaphone扩音器andIhavebeenprivy私下知情todetailsofpeople'slivesthatIwouldrathernotknow.Maybephoneboothscouldserveascellphoneharborstoday. 1WhatfeaturedoestherestaurantinMainetownhave A.Itisverypopular B.Itisold﹣fashioned C.Itwillclosedown D.Ithasbeenneglected 2Asakidtheauthor A.hadafewfriends B.oftencalledhisfriends C.wasnotallowedtoanswerthephone D.learnedthatphoneconversationsareprivate 3Whatistheauthor'sattitudetowardscellphone A.Critical B.Tolerate C.Optimistic D.Approving 4WhatdidtheauthordoinBoston'sSouthStation A.Hetalkedtoanoldfriend. B.Heboughtsomecolorfulroses. C.Heoverheardaman'spersonalinformation. D.Hehelpedastrangerwhowasmakingacall.
Theaye﹣ayeinthesamefamilyaspeoplemonkeysandapesisabout40cmlongwithabushytaleaboutthesamelengthasthebody.Thedarkbrownfurislongandwoollygivingtheanimalarathershaggy蓬松的appearance.TheyarefoundonlyonMadagascaranislandoffthecoastofAfrica.ItlivesinthetropicalforestsintheeastandnorthofMadagascar. Theaye﹣ayeismostlyarboreal栖息在树上的butissometimesseenwalkingontheground.It'sactiveduringthenightlookingaroundinthetreesforfood.Theaye﹣ayeisactuallythelargestprimate灵长类动物activeduringthenight.Largeeyeshelptheaye﹣ayefinditswayaboutatnight.Duringthedaytheaye﹣ayesleepsinanestinatree.Aye﹣ayesspendalmostthewholenighttravellingaboutandfeeding. Aye﹣ayeslivealone.Sometimespairsareseenbutbasicallylittleisknownabouttheirlives.Theydon'tleapandclingtotreeslikeotherprimates.Theymoveaboutonallfourlegs.Theyoccasionallymakebriefcriesbutareusuallysilent.Wormsinsidedeadwoodformthelargestpartoftheaye﹣ayediet.Theaye﹣ayealsofeedsonfruiteggsandbambooshoots. Thefrontfeetoftheaye﹣ayeareunique.Allthetoesarelongandthinbutthethirdisexceptionallylong.Theaye﹣ayetapsonthetreetrunkandlistensformovementasitsearchesforplaceswherewormsmightbelocated.Itbitesatthetreetomakehomesthenitusesitslongthirdfingertoreachinsideandhookoutworms.Thefrontteethoftheaye﹣ayegrowcontinuouslyandareworndownbyitseatingatbarkinitssearchforworms. Aye﹣ayesareclosetobegoneortotallygone.Becauseofdeforestation伐木orforestdestructiontheanimalshavethereforebeenforcedtoeatvillagers'cropsandmanyaye﹣ayeshavebeenkilledwhiledoingso.InadditionsomepeopleonMadagascarwillbelievethatseeinganaye﹣ayeisasignthatsomeoneclosetothemwilldiesotheykilltheanimalsonsight. 1Accordingtothefirstparagraphtheaye﹣aye. A.lookscolorful. B.hasahairlesstail. C.likesthehotplaces. D.soundslikemonkeys. 2Theaye﹣aye'sthirdfingerismainlyto. A.makeholesbigenough B.reachintotheholeforfood C.helpwalkfastontheground D.gettheanimalstofixonthetree 3Whatarereducingthenumberofaye﹣ayes A.People'sactivities. B.Environmentchanges. C.Globalwarming. D.Environmentalprotection. 4Whatisthepurposeofthepassage A.Toprotecttheaye﹣ayes. B.Tostopforestsbeingdestroyed. C.Tomaketheaye﹣ayeslivebetter. D.Tointroducetheaye﹣ayes.
已知函数fx=xlnx﹣axa∈R. 1求函数fx的单调区间 2若fx+a≥0恒成立求a的值.
Indonesiaishometofouroftheworld'sworstpollutedriversandrankssecondwhenitcomestoplasticwaste.Sincesingle﹣usepackagingisalargecontributortotheproblemEvowareanIndonesian﹣basedcompanydecidedtohandlethatissuefirst.Andnowakindofedible可食用的packetshasbeeninvented. Afterinvestigatingvariousmaterialoptionsthecompanysettledonseaweed.Unlikecomcommonlyusedforcontainersseaweeddoesnotrequireresourceslikewaterorlargeamountsofspace.AccordingtoEvowareasmuchas40tonsofseaweedcanbegrowninanareathesizeofabaseballfield.Italsohelpsabsorbharmfulgreenhousegaseslikecarbondioxide.SinceIndonesianfarmersalreadyharvestmoreseaweedthantheycansellitiseasyforthecompanytofindthematerial. ThoughtheywillnotmakepublictheirproductionprocessEvowareannouncestheseaweedpackagingcontainsnochemicalsandissafetoconsume.Inadditiontowrappingfastfooditemsitcanalsobeusedtohousethingslikeinstantnoodleseasoning调味品andinstantcoffee. Thoughtheediblewrappersmaynothaveanytastethesamecannotbesaidaboutthesingle﹣usecupsthatthecompanyhasalsoinvented.Thesingle﹣usecupsthatcanbeusedtoservecolddrinksareavailablewiththetasteoforangeandgreentea. Whilereplacingplasticwiththeseaweedproductsmayseemlikeano﹣brainertomostofusitisahard﹣sellinIndonesia.AccordingtoChristianTheawarenessunderstandingandsenseofurgencytominimizetheuseofsingle﹣useplasticarestillverylow.Alsoafactoristhecostwhichishigherthanusingplastic. HopefullyEvowarewillsucceedinconvincingIndonesiansandpeopleworldwidethatswitchingtotheirproductswillgoalongwayinprotectingourbeautifulplanet. 1WhatisEvoware'spurposeofinventingeatablepackages A.Tomakefulluseofseaweed. B.Tomakegenerousprofits. C.Toattractmorecustomers. D.Toreduceplasticpollution. 2Whatcanwelearnaboutseaweedfromparagraph2 A.Itiseasytoget. B.Itbreaksdowneasily. C.Itishardtoharvest. D.Itcangrowinabaseballfield. 3Howaresingle﹣usecupsdifferentfromseaweedpackaging A.Theyarebeautiful. B.Theyhavedifferenttastes. C.Theyareinvariousshapes. D.Theyareenvironmentallyfriendly. 4Whatstopstheseaweedproductsbeingwidelyused A.Thehighcost. B.Theterribletaste. C.Thelackofseaweed. D.Thecomplexproductionprocess.
TheearthhaschangedoverandoveragainthroughoutthecourseofitshistoryInordertosurviveinchangingenvironmentsspeciesmustoftengothroughaprocessofadaptation.Adaptationreferstogeneticchangethatenablesanorganism生物体suchasananimalorplanttosurviveinitsenvironment.Iftheorganismsofaspeciescannotchangealongwiththeareainwhichtheylivetheyriskdyingout.Recenthistoryhasgivenusanimportantexampleofhoworganismsareabletosurviveoncetheirenvironmentschange. Lightgraypepperedmoths胡椒蛾anddark﹣coloredpepperedmothslivedinthecountrysidebetweenthecitiesofManchesterandLondoninEnglandManyyearsbeforethe19thcenturymoreofthelightgraypepperedmothshadbeenabletosurviveintheirenvironmentmostlybecauseoftheircolor.Birdscouldn'tseethelight﹣coloredmothsonthetreesbecausethecolorofthemothswassimilartothecolorofthetrees. Intheearly19thcenturythoughEnglandbeganthefirstyearsofitsIndustrialRevolution.Manyareasbecameoccupiedbyagrowingnumberoffactories.Manyofthesefactoriesneededcoaltoprovideenergyfortheirmachines.Whencoalbumsitgivesoffalotofdark﹣coloredsmokes.Thetreesbegantoblackenbecauseofallthesmokeintheairfromthefactories.Thismadethelightgraypepperedmothsmuchmorevulnerable.Birdscouldseethemonthetreesmoredearlyandeasilyhuntthemdown. SometimeinthenexthundredyearsscientistsbegantonoticeahugechangeinthemothpopulationlivinginandbetweenthecitiesofManchesterandLondon.Mostofthepepperedmothswereofthedark﹣coloredkind!Whatcausedthischangewasthefactthatbirdshadeatenalotofthelightgraypepperedmothsbecausethemothscouldbeseenclearlyonthedarkenedtrees.Thedark﹣coloredpepperedmothsintheareasurvivedmuchmoreeasilyandmatedwithotherdark﹣coloredpepperedmothsuntilmostofthepopulationofpepperedmothsbecamedark﹣colored. 32.Ifaspeciescan'tadapttothechangingenvironmenttheyarelikelyto. A.bedrivenoutoftheirhabitat. B.becomeextinct C.movetoanotherenvironment D.gothroughgeneticchanges 33.Whatconclusioncanbedrawnfromthechangeintwokindsofmoths A.Therewerepreviouslynodark﹣coloredpepperedmoths. B.Thelight﹣coloredpepperedmothsmovedtoanewenvironment. C.Thecolorchangehadnothingtodowiththechangeintheirenvironment. D.Darkcoloringwasbetterforthepepperedmothssurvivalinthe19thcentury. 34.Whatdoestheunderlinedwordvulnerableprobablymean A.Quicktochange B.Opentoattack C.Easilydefended D.Inastrongposition 35.Whatdoestheauthormainlydescribeinthepassage A.HowtheIndustrialRevolutionimprovedthelivesofworkers. B.Howtheearthchangedthroughoutthecourseofitshistory. C.Howhumaninfluenceorganismsthroughartificialselection. D.Hownaturalselectionchangedthepopulationofpepperedmoths.
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