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已知函数f(x)=|x+2|. (1)求不等式f(x)+f(x﹣2)<x+4的解集; (2)若∀x∈R,使得f(x+a)+f(x)≥f(2a)恒成立,求a的取值范围.
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高三下学期数学《》真题及答案
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Althoughtheideaofzeroemissionnetcarbon﹣positivesustainable可持续developmentwaspromotedworldwidemostcitiesareatalosswhattodoorevensomehaveobjectedtoit.ButinLiuzhouacityinsouthernChinaattitudescouldnotbemoredifferent. TheLiuzhouMunicipalityUrbanPlanningBureauhassignedupItalianarchitectStefanoBoerithefatheroftheforestcitymovementtobuildaself﹣containedcommunityforupto30000people.Heisthego﹣tomanforsuchprojectsthankstothesuccessofhisverticalforeststworesidential住宅的towers.Completedin2014theyremoveupto17.5tonsofsoot煤烟fromtheaireachyearandayearlateroneofthemwasnamedBestTallBuildingWorldwide. TheLiuzhouprojectisamuchmoreambitiousundertakinghowever.Itshomeshospitalshotelsschoolsandofficeswillbebuiltona340﹣acresiteinwhatBoericallsthefirstattempttocreateanurbanenvironmentthatisreallytryingtofindabalancewithnature.Its100speciesofplantlifeareexpectedtoabsorbalmost10000tonsofcarbondioxideand57tonsofpollutantsperyearwhileatthesametimeproducing900tonsoflife﹣givingoxygen. Althoughthearchitectshaven'tpublishedthecostoftheforestcitytheMilantowerscostonlyfivepercentmorethantraditionalskyscrapers. TheconstructionofhisforestcityatLiuzhouissettobeginin2020andthereisstillagreatdealofplanningandresearchrequiredbeforeaprojectedcompletiondatecanbeset.HoweverBoeriremainsoptimisticabouttheprojectandhasconfidenceinthesoundnessofhisvisionIreallythinkthatbringingforestsintothecityisawaytodealwithglobalwarming. 1What'sLiuzhou'sattitudetowardsthesustainabledevelopment? A.Approving. B.Cautious. C.Unfavorable. D.Doubtful. 2WhyisStefanoemployedfortheLiuZhouproject? A.Hevolunteeredtodotheproject. B.Heisafamousarchitectintheworld. C.Heisthefatheroftheforestrecovery. D.Hehasgainedexperienceinsimilarprojects. 3Whatdoestheunderlinedwordtheyreferto? A.Thearchitects. B.Thetwotowers. C.Forestsinthecity. D.Theresidentsofthecity. 4What'sthepurposeofLiuZhouproject? A.Toprovidemorejobs. B.Tobringforestintocity. C.Tosolvehouseshortage. D.Toimprovetheenvironment.
酵母菌进行有氧呼吸和无氧呼吸的共同终产物是
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Asafirstresponderyouneverknowwhattypeofsituationyoumightwalkintoorwhoyou'llmeetalongtheway.That'sdefinitelybeenthecaseforJeffreyLanenberga51﹣year﹣oldparamedic急救医务人员since1984. TenyearsintothejobLanenbergreceivedacallthatreportedthatamaninhisearly30shadfallendownintheMallofAmerica.WhenLanenbergandhispartnerarrivedatthescenetheyfoundtheyoungmalefacedownontheground.Hehadgoneunconsciousmakingweakattemptstobreathe.Hiswifestoodbesidehimholdingtheirsmallsoninhorror.Theyquicklyrushedtodefibrillate除颤andcalmthemantokeephimundercontrol.AfterLanenbergdroppedthepatientoffattheneighboringhospitalhethoughtaboutthemanandhisfamilyforalongtime. LanenbergthoughthehadexperiencedeverythingunderthesununtilonerandomvisittoOfficeMaxthreeyearsagowherehemetamanrepeatedlywalkbackandforthwhilestaringathim.Asitturnedoutthemanwasthepatienthehadsaved20yearsearlier. Yougaveme20yearsmorethanIeverthoughtI'dhavethemansaid.HethankedLanenbergrepeatedlyandtoldhimhehadsomeonehewantedhimtomeet.Hesteppedaroundthecornerandreappearedwitha20﹣something﹣year﹣oldman.Lanenberginstantlyknewthatitwasthesonhehadseenstandingbyhismotherallthoseyearsago. ThatdaychangedmylifeLanenbergsaid.Beforethateverythingwasaboutwork…WhenItalktomybeginner﹣trainingclassItellthemyouneverknowtheimpactyoucanhaveonsomeone'slife. 1WhatdidLanenbergdowiththeyoungman? A.Hegavethemanthefirstaid. B.Hecuredthemanatthescene. C.Heonlysentthemantohospital. D.Hetookcareoftheman'swifeandson. 2WhatdidLanenbergthinkoftheencounterwiththeman? A.Itwasunbelievable. B.Itwasacommonroutine. C.Itwasamatterofcourse. D.Itwasadangeroussituation. 3WhywasthemanthankfultoLanenberg? A.Lanenberghelpedbringuphislittleson. B.Lanenbergdonatedtosupporthisfamily. C.Lanenberggavehimthepresenthappylife. D.Lanenbergtaughthissontobeanewdoctor. 4HowdidthemeetingchangeLanenberg'slife? A.Hechangedhisattitudetohisjob. B.Hewasrewardedwithmuchmoney. C.Hegotapromotiontobeateamleader. D.Hetookupteachingworktotrainnewcomers.
LastweekVodafonestartedatestoftheUK'sfirstfull5GserviceavailableforusebybusinessesinSalford.ItispartofitsplantotrialthetechnologyinsevenUKcities.Butwhatcanweexpectfromthenextgenerationofmobiletechnology? Onethingwewillseeinthepreparationforthetestislotsoftrickswiththenewtech.Earlierthisyearoperatorspaidalmost£1.4billionforthe5Gwavelengthsandtocompensateforthatcashtheywillneedtocatchtheeyeofconsumers.InSeptemberVodafoneuseditsbitoftherangetodisplaytheUK'sfirsthologram全息call.TheManchesterCitycaptainStephHoughtonappearedasaholograminNewbury.Itisn'tallhologramshowever5Gwillofferfasterinternetaccess.withOfcom英国通讯管理局suggestingthatvideothattakesaminutetodownloadon4Gwillbeavailableinjustasecond. Thewiderapplicationistosupportconnectedequipmentontheinternetofthings﹣notjusttheinternet﹣enabledfridgethatcanreorderyourmilkforyoubutthenetworkthatwillenabledriverlesscarsanddeliverydrones无人机tocommunicatewitheachother. ProfWilliamWebbhaswarnedthatthetechnologycouldbeacaseoftheemperor'snewclothes.Muchofthespeedincreaseheclaimscouldhavebeenachievedbyputtingmoremoneyinthe4Gnetworkratherthananewtechnology.OtherdifferentvoiceshavesuggestedthatafocusonrollingoutwiderruralbroadbandaccessandaddressingcurrentnetworkcoveragewouldbemorebeneficialtotheUKasawhole. Obviously5Gwillalsobringacosttoconsumers.Itrequiresahandsetforboth5Gand4Gandthefirst5G﹣enabledsmartphonesareexpectedinthecomingyear.Withtheslowpaceofnetworkrolloutsofaritislikelythatconsumerswillendupupgradingtoanew5Gphonewellbefore5Gbecomeswidelyavailableinthenextcoupleofyears. 1WhydoesProfWilliamWebbsaythetechnologycouldbeacaseoftheemperor'snewclothes? A.Heisinfavoroftheapplicationofthenewtechnology. B.5Gwillbringacosttoconsumersintheirdailylife. C.5Ghelpspeoplecommunicatebetterwitheachother. D.Heprefersmoremoneytobespenton4Gnetworks. 2Theunderlinedwordaddressinginthefourthparagraphhastheclosestmeaningto. A.makingaspeechto B.tryingtosolve C.managingtodecrease D.respondingto 3Thelastparagraphindicatesthat. A.it'lltakeseveralyearstomake5GaccessibletothepublicintheUK B.5Gserviceshowshugedevelopmentpotentialandabroadmarket C.customersareeagertouse5Gsmartphonesinsteadof4Gones D.it'sprobablethat5GnetworkrolloutisspeedingupinBritain 4Whatdoweknowaboutthetext? A.Vodafoneissuccessfulinspreadingthe5Gservice. B.StephHoughtonappearedasahologramby4G. C.Theapplicationof5Gwillmakelifemucheasier. D.5GphonesareavailableinruralareasoftheUK.
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下列各项应用中主要是利用细胞呼吸原理的是 ①手指受伤时选择透气的消毒纱布包扎 ②稻田定期排水有利根的生长 ③利用葡萄粮食和酵母菌制酒 ④大棚种植用无色透明薄膜
下面是光合作用过程示意图请回答问题. 1光合作用包括两个阶段其中E是在叶绿体的进行该阶段需要D阶段提供的物质是. 2叶绿体的色素分布在.图中A是. 3光合作用发生的部位是. A.叶绿素B.叶绿体C.叶绿体的基粒D.叶绿体的基质
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September222018willbeWorldCar﹣FreeDayadayonwhichpeopleacrosstheglobeareencouragedtofind1methodstomeettheirtransportationneedsandre﹣discoverbusesbikesandtheirown2. Onthisdaypeoplegettogetherinthestreetsintersectionsandneighborhoodblocksto3theworldthatwedon'thavetoacceptourcar﹣controlledsociety. While4alongtheselineshadtakenplacefromtimetotimestarting5the1973oilcrisisitwasonlyinOctober19946astructuredcallforsuchprojectswas7inakeynotespeechbyEricBrittonattheInternationalAccessibleCitiesConferenceheldinToledoSpain. ThefirstnationalcampaignwaslaunchedinBritainin1997andtheFrenchfollowedsuitin1998.In2000carBustersissuedanopen8foraWorldCar﹣FreeDayto9withEurope'sCar﹣FreeDayonSeptember22.10thenwehavebeguntocallforcitizenstoorganize11onornearthisday. Howeverwedonotwant12onedayofcelebrationsandthenreturnto13life.WorldCar﹣FreeDayisthe14timetoremindcityplannersandpoliticiansto15cyclingwalkingandpublictransport.Itisuptouscitiesandgovernmentstohelp16permanentchangesto17pedestrianscyclistsandotherpeoplewhodonotdrivecars. While18accomplishmenthasbeenachievedintermsofmediacoveragetheseevents19tobedifficulttoachieverealsuccessandevenadecadelaterthereisconsiderableuncertaintyabouttheusefulnessofthisapproach.Broadpublicsupportand20tochangeisneededforsuccessfulimplementation执行. 1A.effective B.efficient C.useful D.alternative 2A.legs B.motors C.subway D.feet 3A.recall B.remind C.realize D.recommend 4A.projects B.events C.activities D.meetings 5A.as B.on C.with D.beyond 6A.when B.that C.where D.how 7A.undertaken B.submitted C.developed D.issued 8A.answer B.call C.wish D.longing 9A.connect B.involve C.consist D.concern 10A.Since B.Before C.After D.Right 11A.events B.affairs C.incidents D.accidents 12A.even B.still C.just D.ever 13A.usual B.previous C.ordinary D.average 14A.perfect B.limited C.accurate D.correct 15A.givewayto B.givepriorityto C.giveriseto D.giveinto 16A.employ B.decrease C.create D.increase 17A.assist B.benefit C.instruct D.influence 18A.constant B.similar C.envying D.considerable 19A.turnout B.workout C.carryout D.figureout 20A.approach B.attitude C.chance D.commitment
Thereareseveraldifferenttypesoffiredepartments.Somehirefull﹣timepaidfirefightersandsomearerunentirelybyvolunteers.1afirefightermustgothroughstrictphysicalandacademictrainingtoensureastrongknowledgeoffiresafetyandthephysicalstrengthtohandlethetasksrequiredbymembersofafiredepartment. Joiningafiredepartmentrequiresthatbothphysicalandwrittentestsarepassedwithscoresshowingathoroughknowledgeoffiresafety.2. Thefirststepinjoiningafiredepartmentasapaidfirefighteristosubmitanapplicationaswellasacquiretheappropriatetraining.Usuallyfirefightersmusthaveahighschooldiplomaandsomecompletetwo﹣or﹣four﹣yearprogramsinfirescienceatcommunitycollegesanduniversities.3andifacandidatealreadyhasconnectionsatafiredepartmenthemayapplyforapositionstraightoutofhighschool. Onceacandidateappliesandisacceptedfortrainingatafiredepartmenthemustthencompleteseveralweeksoftrainingatthedepartment'strainingcenter.4.Whenthisisdonethecandidateissenttoafirecompanyforaperiodofprobation实习.Hehastocontinuetraininginthenewpositionwhilebeingdirectedbyexperiencedfirefighters.5.Anapplicationmustbesubmittedtothevolunteerfiredepartmenttheniftheapplicationisacceptedthecandidatewilllakeatrainingprogramandthenberequiredtopassaphysicalandwrittentest.Firefightersmustalsobecomecertified认证asEmergencyMedicalTechniciansEMTs.ThelevelofEMTcertificationisdeterminedbytheindividualdepartments. A.Althoughitisdemanding B.Whichevertypeisdesired C.Howeveranacademicprogramisnotrequired D.Forvolunteerfirefighterstheprocedureissimilar E.Butjoiningavolunteerfiredepartmentistotallydifferent F.Trainingconsistsofclassroomworkandpracticaltraining G.Alsoacandidatemustbeabletorespondquicklyinemergencies
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关于内能及其应用已知c水>c煤油下列说法正确的是
标有6V1.5W的小灯泡通过它的电流随两端电压变化的关系如图所示若把这样的三只灯泡串联起来接在12V的电源两端灯泡的实际功率约为W
FromAntiguatoZanzibarfthesespotspromiseanincredibletripfor2019. AntiguaGuatemala Antiguaiswortheverypennybutthatdoesn'tmeanyou'llhavetoemptyyourwalletsaysHudson.Thereareplentyofbudgel﹣carisciousactivities.Itwon'tcostyouacointovisitSantoDomingodelCerroanoutdoorsculpturepark.Wantingsomethingsweet?HeadtoChocoMuseo.Admissionisfreeandsoarethesamples! OdessaUkraine Odessaishavingabitofatourismboomnationwide﹣notthatwe'resurprisedgivenitssandybeachesandpastel﹣coloredbuildings﹣butit'sstillfairlyundertheorderforinternationalaudiences.Youcanalsocountonthisportcityforaffordablefun.TicketstotheOdessaOperaHousestartatamere﹩2! BogotaColombia TravelersonbudgetwillfindColombia'svastcapital.farmoreofabargainandeverybitasfascinatingsaysHudson.It'sfreetovisitMuseodeOroandonSundaysmanyofthebigroadsareclosedtoaccommodatefoodcartsstreetentertainersandpedestrians. Zanzibar Zanzibarattractsvacationerswithitswhitesandbeachesgreenish﹣blueddescolorfulcoralreefsandoceanfrontseaside.OfcoursewanderinginhistoricStoneTownisprettyappealingtoo.Eitherwayyouneedn'tspendapennyinthisamazingplace.It'salsoworthnotingthatJozaniForestistheonlyplaceintheworldyoucan9eeendangeredredcolobusmonkeys. 1Whichofthefollowingrequiresadmissionfee? A.ChocoMuseo. B.StoneTown. C.MuseodeOro. D.OdessaOperHouse. 2WhatisspecialtoZanzibar? A.Whitesandbeaches. B.Colorfulcoralreefs. C.Redcolobusmonkeys. D.HistoricStoneTown. 3Whatdothefourdestinationshaveincommon? A.Theyarecoastalcities. B.Theyareinexpensivetovisit. C.Theywelcomestreetentertainers. D.Theywillmakeyourwalletempty.
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假定你是李华你和几个朋友打算去参观茶园想邀请美国交流生Henry同往.请你给他写封邮件告知活动安排.内容包括 1.时间和地点; 2.学习如何沏茶品茶; 3.介绍中国茶文化的历史和发展. 注意 1.词数100左右; 2.可以适当增加细节以使行文连贯. DearHenry Yours LiHua
如图是三个相邻的植物细胞之间水分流动方向示意图.图中三个细胞的细胞液浓度关系是
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Balletisaformalkindofdanceperformancewitharichandinterestinghistory.ThewordballetcomesfromtheFrenchlanguageand1bebasedontheItalianwordballetto.Ballettomeansalittledance.Ballet'searlyrootsbeganinItalyinthelate1400s.ButitwasinFrance2balletdevelopedintotheformweknowtoday. TheFrenchrulerLouistheFourteenthhadabiginfluence3thedirectionofballetinitsearlyhistory.HeruledFranceforseventy﹣twoyears4startin1643.Hestarteddancingasaboyandworkedharddaily. LouistheFourteenthturnedballetintoaformofdancethatreflected5hepowerandinfluence.Ballet'smanyrulesand6extremedetailedmovementsexpressedaperson'spowerandsocialrelations.Thekingmadesurethatballetbecamea7requireforthepeopleofhiscourt.HealsostartedtheRoyalAcademyofDance8importantpeoplecouldlearnthisart.Theaimofthisdancewasself﹣controlorderandperfection. Balletslowlychangedfromadanceattheking'scourttoone9performbyprofessionaldancers.WhenLouistheFourteenthdiedin1715ballet10bringtoodierpartsofEuropeandwasdevelopinginotherways.
面镜不是使光线透过而是使光反射回去的仪器光线遵循反射定律如图甲是凹面镜它将平行主轴的入射的光线会聚在焦点F上这是因为表面每个点的法线方向不同光线以不同的角度反射根据光路可逆性凹面镜不仅可以使平行光线汇聚于焦点还能使过焦点的光线反射成平行于主轴的光请根据以上叙述在图乙中画出H0的成像光路图.
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