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点P在椭圆C1：＝1上，C1的右焦点为F，点Q在圆C2：x2+y2+6x﹣8y+21＝0上，则|PQ|﹣|PF|的最小值为（ ）
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高二上学期数学《》真题及答案
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已知可行域的外接圆C.与x轴交于点A.1A.2椭圆C.1以线段A.1A2为长轴离心率.1求圆C.及椭
已知可行域 的外接圆C与x轴交于点A1A2椭圆C1以线段A1A2为长轴离心率
已知可行域的外接圆C与x轴交于点A1A2椭圆C1以线段A1A2为长轴离心率1求圆C及椭圆C1的方程2
已知椭圆与双曲线有公共的焦点C2的一条渐近线与以C1的长轴为直径的圆相交于AB两点若C1恰好将线段A
A
B
C
D
已知椭圆C1的方程为双曲线C2的左右焦点分别为C1的左右顶点而C2的左右顶点分别是C1的左右焦点1求
如图已知F1F2是椭圆C.a＞b＞0的左右焦点点P.在椭圆C.上线段PF2与圆相切于点Q.且点Q.为
已知椭圆C.的中心在的点焦点在x轴上F1F2分别是椭圆C.的左右焦点M.是椭圆短轴的一个端点过F1的
已知可行域 的外接圆C与x轴交于点A1A2椭圆C1以线段A1A2为长轴离心率
选修4-4坐标系与参数方程 在直角坐标系xOy中曲线C1的参数方程为以坐标原点为极点以x轴的正半轴
已知椭圆C1抛物线C2的焦点均在x轴上C1的中心和C2的顶点均为原点D从每条曲线上取两个点将其坐标记
已知椭圆C1和抛物线C2有公共焦点F10C1的中心和G2的顶点都在坐标原点过点M40的直线l与抛物
选修4—4坐标系与参数方程 在直线坐标系xOy中曲线C1的参数方程为α为参数以坐标原点为极点x轴正
设椭圆E.＝1的焦点在x轴上.1若椭圆E.的焦距为1求椭圆E.的方程.2设F.1F.2分别是椭圆的左
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现代社会环境问题越来越引起人们的关注可通过膜电池除去污水中的乙酸钠和对氯苯酚同时利用此装置产生的电能进行粗铜的精炼装置如下图所示．下列说法正确的是
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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Playtimeisinshortsupplyforyoungchildrenthesedaysandthelifelongconsequencesfordevelopingchildrencanbemoreseriousthanmanypeoplerealize． AnarticleinthemostrecentissueoftheAmericanJournalofPlaydetailsnotonlyhowmuchchildren'splaytimehasdeclinedbuthowthislackofplayaffectsemotionaldevelopmentleadingtotheriseofanxietydepressionandproblemsofattentionandselfcontrol．Sinceabout1955children'sfreeplayhasbeencontinuallydecliningatleastpartlybecauseadultshaveappliedever﹣increasingcontroloverchildren'sactivities．saystheauthorPeterGrayPh．DProfessorofPsychologyatBostonCollege． Wecandescribetheunstructuredfreely﹣chosenplayasatestinggroundforlife．Itprovidescriticallifeexperienceswithoutwhichyoungchildrencannotdevelopintoconfidentandcompetentadults．Sokidsneedmoreofitnotless．Becauseplayishowyoungchildrenlearnimportantsocialandemotionalskillssuchassharingcooperatingcommunicatingandempathizing．Ithelpsthemdevelopfitbodiesstrongmindsandbraveheartssotheycantakeonnewchallengesandriskysituations． Gray'sarticleismeanttoserveasawake﹣upcallregardingtheeffectsoflostplay．Wemustknowthatlackofchildhoodfreeplaytimeisahugelossthatmustbepaidattentiontoforthesakeofourchildrenandsociety．Butparentswhokeepalookoutoveranddisturbtheirchildren'splayareabigpartoftheproblem．Itishardtofindgroupsofchildrenoutdoorsatallandifyoudofindthemtheyarelikelytobewearingschooluniformsandfollowingthedirectionsofcoacheswhiletheirparentsdutifullywatchandcheer． Actuallywhenchildrenareinchargeoftheirownplayitprovidesafoundationfortheirfuturementalhealthasolderchildrenandadults．Playgiveschildrenachancetofindanddevelopaconnectiontotheirownself﹣identifiedandself﹣guidedinterest．Itisthroughplaythatchildrenfirstlearntomakedecisionssolveproblemsimproveself﹣controlandfollowrules．Playhelpschildrenmakefriendsandlearntogetalongwitheachotherasequals．Mostimportantlyplayisasourceofhappiness． Whenparentsrealizethemajorrolethatfreeplaycantakeinthedevelopmentofemotionallyhealthychildrenandadultstheymaywishtoreassesstheprioritiesrulingtheirchildren'slives．Theneedsforchildcareacademicandathleticsuccessandchildren'ssafetyisimportant．Butperhapsparentscanbegintoidentifysmallchanges﹣﹣suchasopeningsintheschedulebackingofffromquitesomanysupervised有监督的activitiesandpossiblyslightlylesskeepingwatchontheplaygroundthatwouldstarttheslowreturningtothedirectionoffreeimaginative﹣directedplay． 1Whatdoweknowfromthefirsttwoparagraphs A．Theriseofchildren'sanxietyismoreseriousthanpeoplerealize． B．Lackofplaytimeleadstokids'unhealthyemotionaldevelopment． C．Moreyoungchildrenaresufferingfromdepressionduetofreeplay． D．Playingtoomuchleadstoproblemsofkids'attentionandselfcontrol． 2AccordingtoPeterGrayunstructuredfreely﹣chosenplay． A．isfullofchallengesandriskysituations B．shouldbebalancedwithadult﹣directedactivities C．doesharmtochildren'sconfidenceandcompetence D．hasgoodeffectonchildren'ssocialandemotionalskills 3Thearticleisintendedfor． A．parents B．teachers C．coaches D．children 4Whichofthefollowingwouldbethebesttitleforthetext A．DoChildrenNeedMoreSelf﹣guidedPlay B．AreChildrenInterestedinGuidedPlay C．CanChildrenGuideThemselves D．AreChildren'sProblemsSerious
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．
假段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． Squaredancinghasbeenmoreandmorepopularwiththeelderlyastheirlivingconditionsimprove．Mostpeoplethoughtitcanhelppeopletakeregularlyexerciseandstrengthentheirfitness．Besidesitprovidespeoplemorechancestotakeactivityoutdoors．Howeversomepeoplearguethatthemusicisverynoisythatdisturbsthesurroundingcitizens'normallife．Alsobeexposedtosuchloudnoisemaydoaharmtotheirhealthinthelongrun． Inmyopinionsquaredancingisagoodformofexercisesodancersshouldtakeourneighbors'needsintoconsideration．Iftheychoosearighttimeandturndownthemusicitwillcausefewertroubleforothers．
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
J是一种解热镇痛类药物其合成路线如下 已知部分信息如下 ①苯环上原有取代基对苯环上新导入的取代基的位置有一定的影响例如一OH一CH3等易使新导入的取代基进入苯环的邻对位一NO2一COOH等易使新导入的取代基进入苯环的间位． ②具有弱碱性和还原性 ③J遇氯化铁溶液能发生显色反应其苯环上一氯代物只有2种且结构中苯环直接连接“R﹣CONH﹣”基． 回答下列问题 1H的名称是C所含官能团名称是． 2E→F的反应类型是． 3利用下列仪器进行检测时H和I显示的信号完全相同的是测定J所含化学键和官能团的是． a．红外光谱仪b．质谱仪c．元素分析仪d．核磁共振氢谱仪 4D+I→J的化学方程式为． 5在J的同分异构体中同时满足下列条件的有种不包括立体异构． ①能发生银镜反应和水解反应②该物质与足量NaOH溶液反应最多消耗2moNaOH 其中在核磁共振氢谱上有5个峰且峰的面积比为12222的结构简式为． 6已知笨环直接与甲基相连时甲基可被酸性高锰酸钾溶液直接氧化成羧基参照上述流程和信息以甲苯为原料其他试剂自选合成设计合成路线为．
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
采用H2或CO催化还原NO以达到消除污染的目的在氮氧化物尾气处理领域有着广泛应用．回答下列问题 1用CO处理NO时产生两种无毒无害的气体该反应的氧化产物为． 2已知氢气的燃烧热为285.8kJ/mol 2NOg＝N2g+O2g△H＝﹣180.5kJ/mol H2Og＝H2O1△H＝﹣44kJ/mol 写出用H2处理NO生成水蒸气和1molN2的热化学方程式． 3针对上述H2处理NO生成水蒸气和1molN2的反应回答下列问题 ①研究表明上述反应中正反应速率为v正＝k正c2NOc2H2其中k正为速率常数此处只与温度有关．当t＝t1时v正＝v1若此刻保持温度不变将cNO增大到原来的2倍cH2减少为原来的v正＝v2．则有v1v2填“＞”“＜”或“＝” ②在温度T下容积固定的密闭容器中充入3molNO和2molH2发生上述反应起始压强为p0一段时间后反应达到平衡此时压强p＝0.9p0则NO的平衡转化率aNO＝结果保留三位有效数字该反应的平衡常数Kp＝用含p的代数式表示Kp为以分压表示的平衡常数且某气体的分压＝总压×该气体的物质的量分数 4实验室常用NaOH溶液吸收法处理NOx反应方程式如下已知NO不能与NaOH溶液反应． NO+NO2+2NaOH＝2NaNO2+H2O 2NO2+2NaOH＝NaNO2+NaNO3+H2O ①若NOx此处为NO和NO2的混合气体能被NaOH溶液完全吸收则x的取值范围为． ②1molNO2和溶质物质的量为1mol的NaOH溶液恰好完全反应后溶液中各离子浓度由大到小的顺序为． 5一氧化氮﹣空气质子交换膜燃料电池将化学能转化为电能的同时实现了制硝酸发电环保三位一体的结合其工作原理如果所示写出放电过程中负极的电极反应式若过程中产生2molHNO3则消耗标准状况下O2的体积为L．
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．
设NA为阿伏伽德罗常数的值．下列说法错误的是
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
已知乙醇乙醛的沸点分别为78℃20.8℃．某同学试图利用下列实验装置来完成“乙醛的制备收集和检验”一系列实验其中设计不合理的是
Dujiangyanistheoldestman﹣madewatersystemintheworldand1wonderinthedevelopmentofChinesescience．Builtover2200yearsagoin2isnowSichuanProvinceinSouthwestChinathis3amazewatersystemisstilluesedtoday． InancienttimestheregioninwhichDujiangyannowstands4sufferfromregularfloodscausedbytheoverflowforthewaterfromtheMinjiangRiver．5helpthevictimsofthefloodingLiBingtheregiongovernortogetherwithhissondecidedtofinda6solve．LidesignedaseriesofchannelsbuiltatdifferentlevelsalongMountYuleithatwouldtakeawaythefloodwaterwhileleavingtheriverflowingnaturally．7goodstilltheextrawatercouldbedirectedtothedryChengduPlainmakingitsuitableforfarming． Oncethesystemwasfinishednomorefloodsoccurredandthepeoplewereabletolivepeacefully．TodayDujiangyanisadmiredbyscientistsfromaroundtheworldbecauseofonefeature．Unlikemoderndams8thewaterisblockedbyahugewallDujiangyanstillletswaterflowthroughtheMinjiangRivernaturally9enabletheecosystemsandfishpopulationstoexist10harmony．
元素XYZ和Q在周期表中的位置如图所示其中元素Q位于第四周期XYZ原子的最外层电子数之和为17．下列说法正确的是
假设你是红星中学高三学生李华你的英国朋友Jim在邮件中表示下周将到北京参加一个主题为游学在北京的文化体验活动向你咨询有关景点的信息．请给他回邮件内容包括 1．推荐一个特色景点 2．说明理由 3．温馨提示． 注意1．词数不少于50 2．开头和结尾已给出不计入总词数． DearJim Yours LiHua
__NaCN是一种基本化工原料同时也是一种剧毒物质．一旦泄漏需要及时处理一般可以通过喷洒双氧水或过硫酸钠Na2S2O8溶液来处理以减轻环境污染． I．1NaCN用双氧水处理后产生一种酸式盐和一种能使湿润的红色石蕊试纸变蓝的气体该反应的化学方程式是． Ⅱ．工业制备过硫酸钠的反应原理如下 主反应NH42S2O8+2NaOHNa2S2O8+2NH3↑+2H2O 副反应2NH3+3Na2S2O8+6NaOH6Na2SO4+6H2O+N2 某化学小组利用上述原理在实验室制备过硫酸钠并用过硫酸钠溶液处理含__的废水． 实验一实验室通过如下图所示装置制备Na2S2O8． 2装置中盛放双氧水的仪器名称是． 3装置a中反应产生的气体需要持续通入装置c的原因是． 4上述装置中还需补充的实验仪器或装置有填字母． A．温度计B．洗气瓶C．水浴加热装置D．环形玻璃搅拌棒 实验二测定用过硫酸钠溶液处理后的废水中__的含量． 已知①废水中__的最高排放标准为0.50mg/L． ②Ag++2CN﹣═[AgCN2]﹣Ag++I﹣═AgI↓AgI呈黄色且CN﹣优先与Ag+反应．实验如下取IL处理后的NaCN废水浓缩为10.00mL置于锥形瓶中并滴加几滴KI溶液作指示剂用1.0×10﹣3mol/L的标准AgNO3溶液滴定消耗AgNO3溶液的体积为5.00mL． 5滴定终点的现象是． 6处理后的废水中__的浓度为mg/L处理后的废水是否达到排放标准填“是”或“否”． Ⅲ．7常温下含硫微粒主要存在形式受pH影响．利用电化学原理用惰性电极电解饱和NaHSO4溶液也可以制备过硫酸钠．已知在阳极放电的离子主要为HSO4﹣则阳极反应方程式为．
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
假设你是红星中学高三1班学生李华．请根据以下四幅图的先后顺序写一篇英文周记记录你参加学校丝绸之路知识竞赛的全过程． 注意词数不少于60．
SavingDuketurnedouttobeoneofthebestdecisionsJennahadevermade．Littledidthisfamilyknowtheywereabouttobeextremely1foradoptingDuke．Sixyearslateritbecameapparentjusthow2Dukeistothefamily．This3camewhenJennagavebirthtotheirsecondchildabeautifullittlegirlcalledHarper． InearlyOctober2012Harperwasonlynineweeksoldwhensomethingunusualoccurred．Duke4MomandDadinthemiddleofthenightwiththemostabnormalbehavior．DukejumpeduponJennaandEric'sbedandbeganshakingfromheadtotoe．Itwassuch5behaviortoseefromsuchatypicallywell﹣behaveddog．AtfirstJennaandErictriedto6thedogbutthentheythoughtthedogmightbe7thiswayforanotherreason．SureenoughEricquicklyraninto8onHarperandwasshockedbywhathesaw． Harperlookedjustlikeadoll．Shewent9hereyesglassyandherfigureunmoving．Theirnewbabywasn'tbreathingandtheparentsneededto10quickly．FortunatelyJenna11Harperhardonthebackandthebabybeganbreathingagain．Theparentswereimmediatelyfloodedwith12butitdidn'ttakelongforthatrelieftoturntogratitudetoDuke．ItappearedHarper's13hadbeencausedbyacidreflux胃酸倒流．Consequentlysheendedup14ontheup﹣swallow．15Duketheparentswouldhavesleptrightthroughit． 16thecaseofDukereceivedwidepublicity．Werescuedhimandhe17usbyrescuingourdaughterduringanemergencyJennatearfullytoldcameras18therescuehappened．Dukewithnodoubtisaherotous． Indeedheroesare19fromlove．Themoreyoulovethemthemoretheyloveyou．Sosaveadogandgiveita20tosaveyoutoo． 1A．regretful B．grateful C．delighted D．worried 2A．generous B．sensitive C．mean D．vital 3A．realization B．admiration C．news D．relationship 4A．annoyed B．interested C．attacked D．surprised 5A．brave B．rude C．strange D．normal 6A．calmdown B．pickup C．playwith D．believein 7A．barking B．jumping C．reacting D．rushing 8A．check B．wait C．spy D．focus 9A．mad B．hungry C．red D．pale 10A．recover B．act C．call D．run 11A．laid B．threw C．hit D．took 12A．disappointment B．relief C．anxiety D．satisfaction 13A．mistake B．puzzle C．disability D．problem 14A．choking B．breathing C．pausing D．flowing 15A．Thanksto B．Butfor C．Inspiteof D．Regardlessof 16A．Hopefully B．Naturally C．Honestly D．Sadly 17A．repaid B．betrayed C．treated D．supported 18A．before B．when C．since D．after 19A．protected B．respected C．spread D．made 20A．life B．home C．chance D．hand
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．
钛Ti被誉为第三金属广泛应用于航空航天等领域．四氯化钛TiCl4是生产金属钛的重要原料某小组设计实验制备四氯化钛并验证其产物CO装置如下 已知部分信息如下 ①制TiCl4的反应原理为TiO2S+2Cs+2Cl2gTiCl4g+2COg②四氯化钛的熔沸点分别为﹣24℃136℃易挥发在水或淛湿空气中都极易水解加热时能被O2氧化 回答下列问题 1气流由左至右装置的正确连接顺序为AHE填字母． 2A中盛装盐酸的仪器名称是G装置的作用是． 3写出A中发生反应的化学方程式实验室欲制备6720mLCl2标准状态则理论上应转移mol电子． 4能证明上述反应有CO生成的实验现象是． 5利用如图所示装置测定产品纯度取wgTiCl4产品进行实验向安全漏斗中加入适量蒸馏水待四氯化钛充分反应后将烧瓶和漏斗中的液体一并转入锥形瓶中滴加几滴0.1mol•L﹣1的K2CrO4溶液作指示剂注明Ag2CrO4呈砖红色用cmol•L﹣1AgNO3溶液滴定至终点消耗滴定液VmL．【已知常温下KspAgCl＝1.8×10﹣10KspAg2CrO4＝1.1×10﹣12．TiCl4+2+nH2O＝TiO2•nH2O↓+4HCl】 ①安全漏斗在本实验中的作用除加水外还有． ②根据上述数据计算该产品的纯度为用含wc和V的代数式表示．
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．
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