首页
试卷库
试题库
当前位置：
X题卡
>
所有题目
>
题目详情
市面上有某品牌A型和B型两种节能灯，假定A型节能灯使用寿命都超过5000小时．经销商对B型节能灯使用寿命进行了调查统计，得到如下频率分布直方图： 某商家因原店面需重新装修，需租赁一家新店面进行周...
查看本题答案
包含此试题的试卷
高三下学期数学《》真题及答案
点击查看
你可能感兴趣的试题
学校准备购进一批AB两型号节能灯已知2只A型节能灯和3只B型节能灯共需31元1只A型节能灯和2只B
节约能源从我做起.为响应长株潭两型社会建设要求小李决定将家里的4只白炽灯全部换成节能灯.商场有功率为
某商场销售AB两种品牌的节能灯每盏售价B种节能灯比A种节能灯多10元且花费150元购买A种节能灯与
某商场销售A.B.两种品牌的节能灯每盏售价B.种节能灯比A.种节能灯多10元且花费150元购买A.种
吉林小王家里装修他去商店买灯商店柜台里现有功率为100瓦的白炽灯和40瓦的节能灯它们的单价分别为2元
学校准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需26元3只A型节能灯和2只B型节能灯共
节能灯根据使用寿命分成优等品正品和次品三个等级其中使用寿命大于或等于8000小时的节能灯是优等品使
小王家装修他去商店买灯商店柜台里分别有100瓦的白炽灯和40瓦的节能灯它们的单价为2元和32元两种
为了节能减排我市某校准备购买某种品牌的节能灯已知3只A型节能灯和5只B型节能灯共需50元2只A型节
工厂准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需26元3只A型节能灯和2只B型节能灯共
小刚为书房买灯现有两种灯可供选购其中一种是9W即0.009kW的节能灯售价49元／盏另一种是40W即
学校准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需26元3只A型节能灯和2只B型节能灯共
学校准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需26元3只A型节能灯和2只B型节能灯共
节能灯根据使用寿命分成优等品正品和次品三个等级其中使用寿命大于或等于8000小时的节能灯是优等品使用
学校准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需18元3只A型节能灯和2只B型节能灯共需
学校准备购进一批节能灯已知1只A.型节能灯和3只B.型节能灯共需26元3只A.型节能灯和2只B.型节
自有品牌节能灯按形状分有
U型节能灯
螺旋节能灯
球型节能灯
烛型节能灯
小刚为书房买灯现有两种灯可供选购其中一种是9瓦的节能灯售价为49元/盏另一种是40瓦的白炽灯售价为1
某公司租用一个门店作展馆准备对其公司生产的某型产品进行为期一年的展出．为此需对门店进行装修展出结束
学校准备购进一批节能灯已知1只A型节能灯和3只B型节能灯共需26元3只A型节能灯和2只B型节能灯共
热门试题
更多
Whenyouhavegotalotofstuffdecluttering整理yourhomecanbereallynecessary.Declutteringisjustaboutputtingnewsystemsintoplaceinyourlife.1yourealizehowgreatyoufeelaboutitandyouwanttokeepgoing. Gettingridofthingsgivesyoutimetolookafteryourself.2orlookingforthepotatopeeler﹣becauseeverythinghasahomeandyouknowexactlywhereitis﹣you'refreetospendthattimeonyourselfandyourfamily.It'sliberating. 3.Ithastakenyoualongtimetogeteverythingandyouwon'tbeabletogetridofitallstraightaway.Ifyou'repushedfortimethereareeasywaysofintroducingdeclutteringintoyourlife.Spend10minutesadaydeclutteringorifthat'snotmanageabledeclutterthreeitemsaweek. Havethreepiles:oneforthingsyou'regoingtokeeponeforthingsthatareamaybeandoneforthingsyou'regoingtogiveaway.Youwillalsoneedsomebinbagsforrubbish.Arevisitingpileisimportantifyou'restrugglingtogetridofthings.4.MoreoftenthannotyouendupsayingactuallyIdon'tneedthat. Stayfocused.Peopleoftengetsidetrackedwhenthey'retryingtodeclutter.Theystarttryingonclothestheyhadforgottenaboutorlookingatoldphotos.Anothercommonmistakeistojustmovethingsfromplacetoplaceinsteadofgettingridofthem.5. A.Onceyoustartdecluttering B.Youneedtimetoreflectonwhattokeep C.Don'texpecttodecluttereverythingovernight D.Whenyou'renotalwayslookingforthescissors E.Ifyourealisethatyouownsixwineopenerskeeponlyone F.Startthedeclutteringprocessbeforeyoumoveinwithanewpartner G.Youcanjustleavethingsthereforafewweeksbeforeafinaldecision
在平面直角坐标系xOy中直线l的普通方程是xsinα﹣ycosα=0＜α＜π曲线C1的参数方程是φ为参数在以O为极点x轴的正半轴为极轴建立的极坐标系中曲线C2的极坐标方程是ρ=2sinθ． 1写出1及C1的极坐标方程 2已知1与C1交于OM两点l与C2交于ON两点求|ON|2+|OM|的最大值．
Duringtherosyyearsofelementaryschool小学Ienjoyedsharingmydollsandjokeswhichallowedmetokeepmyhighsocialstatus.Iwasthequeenoftheplayground.Thencamemytweensandteensandmeangirlsandcoolkids.TheyroseintheranksnotbybeingfriendlybutbysmokingcigarettesbreakingrulesandplayingjokesonothersamongwhomIsoonfoundmyself.Popularityisawell﹣exploredsubjectinsocialpsychology.MitchPrinsteinaprofessorofclinicalpsychologysortsthepopularintotwocategories:thelikableandthestatusseekers.Thelikables'plays﹣well﹣with﹣othersqualitiesstrengthenschoolyardfriendshipsjump﹣startinterpersonalskillsandwhentappedearlyareemployedeverafterinlifeandwork.Thenthere'sthekindofpopularitythatappearsinadolescence:statusbornofpowerandevendishonorablebehavior.EnviableasthecoolkidsmayhaveseemedDr.Prinstein'sstudiesshowunpleasantconsequences.Thosewhowerehighestinstatusinhighschoolaswellasthoseleastlikedinelementaryschoolare'mostlikelytoengage从事indangerousandriskybehavior.'InonestudyDr.Prinsteinexaminedthetwotypesofpopularityin235adolescentsscoringtheleastlikedthemostlikedandthehighestinstatusbasedonstudentsurveys调查研究.'Wefoundthattheleastwell﹣likedteenshadbecomemoreaggressiveovertimetowardtheirclassmates.Butsohadthosewhowerehighinstatus.Itclearlyshowedthatwhilelikabilitycanleadtohealthyadjustmenthighstatushasjusttheoppositeeffectonus.'Dr.Prinsteinhasalsofoundthatthequalitiesthatmadetheneighborswantyouonaplaydate﹣sharingkindnessopenness﹣carryovertolateryearsandmakeyoubetterabletorelateandconnectwithothers.InanalyzinghisandotherresearchDr.Prinsteincametoanotherconclusion:Notonlyislikabilityrelatedtopositivelifeoutcomesbutitisalsoresponsibleforthoseoutcomestoo.'Beinglikedcreatesopportunitiesforlearningandfornewkindsoflifeexperiencesthathelpsomebodygainanadvantage'hesaid.1Whatsortofgirlwastheauthorinherearlyyearsofelementaryschool?A.Unkind.B.Lonely.C.Generous.D.Cool.2Whatisthesecondparagraphmainlyabout?A.Theclassificationofthepopular.B.Thecharacteristicsofadolescents.C.Theimportanceofinterpersonalskills.D.Thecausesofdishonorablebehavior.3WhatdidDr.Prinstein'sstudyfindaboutthemostlikedkids?A.Theyappearedtobeaggressive.B.Theytendedtobemoreadaptable.C.Theyenjoyedthehigheststatus.D.Theyperformedwellacademically.4Whatisthebesttitleforthetext?A.BeNice﹣YouWon'tFinishLastB.TheHighertheStatustheBetterC.BetheBest﹣YouCanMakeItD.MoreSelf﹣ControlLessAggressiveness
如图在棱长为2的正方体ABCD﹣A1B1C1D1中EFG分别是棱ABBCCC1的中点P是底面ABCD内一动点若直线D1P与平面EFG不存在公共点则三角形PBB1的面积的最小值为
Nowadayspeopletendtodigitaliseeverythingfromwatchestofridges.Itseemsyoucanchooseanyitemlabeledassmart.1Howeverthereareplentythatcanbeusedtoreduceemissionsandsavemoney. Ifyou'reapartofthedigitalisationmovementyoumightbeinterestedintheconceptofsmarthomes.Itmeansthateveryelementofyourhousecanbecontrolledfromapanelonthewalloryourphone.2Useyourmobiletopowerthemonoroffandyoumayfeeltrulymodernortrulylazy.Asidesfromthebenefitsoflivingamorecomfortablelifethispresentsanopportunitytocutdownonyourelectricalbills. Electricitygenerationtodayrepresents31%oftotalglobalfossilfueluseandaround40%ofallenergy﹣relatedCO2emissions.3Itisconsideredasthefirststeptopreventglobalclimatechange.Connectasmartthermometertotheheatingandcoolingsystemandsetaspecifictemperatureatwhichtheheatingbeginstowork.Doingsotheroomwillbeatadesiredtemperaturewhennecessaryandswitchesonapower﹣savingmodewhennotoccupied.SimilarlybyinstallingaCO2sensoryoucanhaveanautomatedventilation通风system.4 Ina150000m2officecomplexnearMunichcalledCampeonenergycostsofupto117067Euroweresavedaftertheuseofenvironmentalcontroldevicesthisyear.InthiswaytheyarecontributingtoalargedecreaseinCO2emissions.Clearlysmarthomesareaboutmuchmorethanjustlivingacomfortablelife.5 A.Itisactuallyaboutlivingagreenlife. B.Smartdeviceshavebeeninstalledworldwidenowadays. C.ItstartsworkingonlywhenCO2concentrationsreachacertainlimit. D.Thereseemtobeanoceanofsuchso﹣calledsmartinventions. E.Bearingthisinmindmeasuresshouldbetakentomakebuildingsmoreenergy﹣efficient. F.Alternativeenergymustbediscoveredbeforethefossilfuelrunsoutinthefuture. G.Thisincludesbasicssuchasheatingandlightingandmanyotherappliances.
1Whatwas'GreenBook'originallyinthe1960s?A.Adocumentaryrecordingthelifeoftheblacks.B.AguidebookforAfrican﹣Americanroadtrippers.C.Abookteachingtheblackstotobetolerant.D.Astoryaboutablackandawhiteonatour.2Whatdoes'ticklesthekeys'suggestaboutShirleyinPara3?A.Heperformsinhistour.B.HehelpsLiptogivethethugsabeat.C.HegetsusedtoLip'sbehaviors.D.Hedrivesthecar.3Whodoestheauthorthinkhighlyofintheend?A.Theauthorofthefilm.B.GreenBookinthe1960s.C.Thecritics.D.Thefilmactors.
小华爱好玩飞镖现有如图所示的由两个边长都为2的正方形ABCD和OPQR构成的标靶图形如果O点正好是正方形ABCD的中心而正方形OPQR可以绕O点旋转则小华随机向标靶投飞镖射中阴影部分的概率是
Everyyearabout40000peopleattempttoclimbKilimanjarothehighestmountaininAfrica.They1withthemlotsofwaste.The2mightdamagethebeautyoftheplace.Theglaciers冰川aredisappearingchangingthe3ofKilimanjaro. HearingthesestoriesI'm4abouttheplace﹣otherdestinationsaredescribedaspurernaturalexperiences. HoweverIsoon5thatmuchhaschangedsincethedaysofdisturbingreportsof6amongtonsofrubbish.Ifinda7mountainwithtoiletsatcampsandalongthepaths.Theenvironmentalchallengesare8buttheeffortsmadebytheTanzaniaNationalParkAuthorityseemtobe9. ThebestofaKilimanjaro10inmyopinionisn'treachingthetop.Mountainsare11asspiritualplacesbymanycultures.This12isespeciallyevidentonKilimanjaroas13gothroughfiveecosystems生态系统inthespaceofafewkilometers.Atthebaseisarainforest.Itendsabruptlyat3000meters14landsoflowgrowingplants.Furtheruptheweather15﹣lowcloudsenvelopethemountainsideswhicharecoveredwiththickgrass.I16twelveshadesofgreenfromwhereIstand.Above4000metersisthehighland17:gravel砾石stonesandrocks.18youclimbintoanarctic﹣likezonewith19snowandtheglaciersthatmaysoondisappear. DoesKilimanjaro20itsreputationasacrowdedmountainwithlinesoftouristsruiningtheatmosphereofpeace?Ifoundtheoppositetobetrue. 1A.keep B.mix C.connect D.bring 2A.stories B.buildings C.crowds D.reporters 3A.position B.age C.face D.name 4A.silent B.skeptical C.serious D.crazy 5A.discover B.argue C.decide D.advocate 6A.equipment B.grass C.camps D.stones 7A.remote B.quiet C.all D.clean 8A.new B.special C.significant D.necessary 9A.payingoff B.spreadingout C.blowingup D.fadingaway 10A.atmosphere B.experience C.experiment D.sight 11A.studied B.observed C.explored D.regarded 12A.view B.quality C.reason D.purpose 13A.scientists B.climbers C.locals D.officials 14A.holdingonto B.goingbackto C.livingupto D.givingwayto 15A.changes B.clears C.improves D.permits 16A.match B.imagine C.count D.add 17A.village B.desert C.road D.lake 18A.Obviously B.Easily C.Consequently D.Finally 19A.permanent B.little C.fresh D.artificial 20A.enjoy B.deserve C.save D.acquire
假定你是李华.最近你校的英语戏剧社社团EnglishDramaClub需要招募一批新成员你打算加入.请根据所给提示写一封自荐信.内容包括: 1.自我介绍包括兴趣和优势 2.参加这个社团的目的 3.希望被批准 注意:1.词数100左右 2.开头和结尾已给出但不计入总词数. DearSirorMadam I'mLiHuafromClass1Grade1. Yourssincerely LiHua
ForCanaanElementary'ssecondgradeinPatchogueN.Y.todayisspeechdayandrightnowit'sChrisPalaez'sturn.The8﹣year﹣oldisthejokeroftheclass.Withshiningdarkeyesheseemslikethekindofkidwhowouldenjoypublicspeaking.Buthe'snervous.'I'mheretotellyoutodaywhyyoushouldshould'Christripsonthe'﹣ld'apronunciationdifficultyformanynon﹣nativeEnglishspeakers.HisteacherThomasWhaleyisnexttohimwhisperingsupport.'Voteforme'ExceptforsomestumblesChrisisdoingamazinglywell.WhenhebringshisspeechtoaniceconclusionWhaleyinvitestherestoftheclasstopraisehim.AsonofimmigrantsChrisstartedlearningEnglishalittleoverthreeyearsago.Whaleyrecalls回想起howatthebeginningoftheyearwhencalledupontoreadChriswouldexcusehimselftogotothebathroom.LearningEnglishasasecondlanguagecanbeapainfulexperience.Whatyouneedisagreatteacherwholetsyoumakemistakes.'Ittakesalotforanystudent'Whaleyexplains'especiallyforastudentwhoislearningEnglishastheirnewlanguagetofeelconfidentenoughtosay‘Idon'tknowbutIwanttoknow.''Whaleygottheideaofthissecond﹣gradepresidentialcampaignprojectwhenheaskedthechildrenonedaytoraisetheirhandsiftheythoughttheycouldneverbeapresident.Theanswerbrokehisheart.Whaleysaystheprojectisaboutmorethanjustlearningtoreadandspeakinpublic.Hewantsthesekidstolearntoboast夸耀aboutthemselves.'Boastingaboutyourselfandyourbestqualities'Whaleysays'isverydifficultforachildwhocameintotheclassroomnotfeelingconfident.'1WhatmadeChrisnervous?A.Tellingastory.B.Makingaspeech.C.Takingatest.D.Answeringaquestion.2Whatdoestheunderlinedword'stumbles'inparagraph2referto?A.Improperpauses.B.Badmanners.C.Spellingmistakes.D.Sillyjokes.3WecaninferthatthepurposeofWhaley'sprojectisto.A.helpstudentsseetheirownstrengthsB.assessstudents'publicspeakingskillsC.preparestudentsfortheirfuturejobsD.inspirestudents'loveforpolitics4WhichofthefollowingbestdescribesWhaleyasateacher?A.Humorous.B.Ambitious.C.Caring.D.Demanding.
已知命题pm∈02命题q双曲线的离心率e则p是q的
某四面体三视图如图所示则该四面体最长的棱长与最短的棱长的比是
TheSpanishsculptorIsaacCordalseesthecityashisplayground.Hespecializesinminiatureastreetartoftenrepresentingasocialcommentaryasacriticalobservationoncapitalismpowerandsoon.Cordalfirstmodelsthesculpturesinclaythenreproducesthemincement水泥about15cminheight.'Asamaterialcementseemsverysymbolicbecauseitisoneofourmostrecognizablefootprintsagainstnature.'hesays.'Todaywehavebeentoousedtocementcityhabitat.'Forseveralyearshe'sbeenworkingontheprojectCementEclipsesreferringtothestatewhenabuildingcoversthesun:'It'sacriticalreflectionontheideaofprogress.'ThesetinycementfigureshaveappearedincitiesacrossEuropefoundsittingontopofbussheltersordrowninginthegrasslandofthebigcity.'ThestreetbecameaperfectsettinginwhichIcouldfindenoughlandscapesforthem.Duetotheirsmallsizeandcolortheygoreallywellintotheurbanenvironment.Theyevennormallygounseenbypassersby.I'mveryinterestedinthatmomentofsurprisewhensomeoneaccidentallydiscoversthem.'hesays.'Nowadaysthereisafearofnotbeingseeninthepublicareasoeverythingisalwaysbigandbold.Webecomeaproductofthisanddonotfocusinasmuch.Ithinkitisgoodtopayattentiontosmalldetails.Myworkisarewardforthosewhodoanditallowsustounderstandandchangetheworldwehavecreatedinadifferentangle.'Cordalsays.1Whichofthefollowingbestexplains'miniature'Underlinedinparagraph1?A.Tinysculpture.B.Smallplayground.C.Socialcomments.D.Criticalobservation.2What'sCordal'sattitudetowardcementcityhabitat?A.Indifferent.B.Critical.C.Neutral.D.Supportive.3WhatdoesCordalintendtotellusinthelastparagraph?A.Everythingbiginpublicisattractive.B.Beingsmallmaybeafearinpublic.C.Weneedtofocusonthedetailsoftheproducts.D.Hisworkhelpsustoseetheworlddifferently.4Whatdoesthetextmainlytalkabout?A.Cordalandhisstreetart.B.Waystobeasculptor.C.Materialsusedforsculptures.D.Reflectionsoncityprogress.
AlbertEinsteinthegeniusbehindthetheoryofrelativityhasrecentlybeenmakingheadlinesagain.Howeverthistimeitisnotforanewscientificbreakthrough1forahandwrittennotehegaveabellboy95yearsago. InOctober1922EinsteinwasdeliveringaseriesoflecturesinJapan2hereceivedatelegraminforminghimthathe3awardtheNobelPrizeforPhysics. Though4pleaseatthenewstheNobelwinnerdecidedtocontinuewithhisJapanesetripinsteadof5headtoStockholmtoacceptthehonor. WhileinTokyohepenned6noteinGermansayingAquietandhumblelifewillbringmore7happythanthepursuitofsuccess…PerhapshehadnoloosechangetotipabellboycomingtodeliverthemessagehegavehimthenoteandtoldhimMaybeifyouareluckythenote8becomemorevaluablethanjustaregulartip. Earlierthisyearthebellboy'snephewdecidedtohandittoJerusalem﹣basedWinner'sAuctions拍卖andExhibitions.Thenotewasthenputupforauction9mightbringtheownerasurprising$1.56million10aEuropeanbuyer.ItwasarecordforanauctionofadocumentinIsraelandthewild﹣hairedscientistdeservedit.
中国古代数学家朱世杰所著算学启蒙一书中提到关于“松竹并生”的问题松长五尺竹长两尺松日自半竹日自倍松竹何日而长等．意思是“现有松树高5尺竹子高2尺松树每天长自己高度的一半竹子每天长自己高度的一倍问在第几天会出现松树和竹子一般高”如图是源于其思想的一个程序框图若输入x=5y=2问输出n的结果为
已知复数z满足z+ii＝2﹣3i则|z|＝
Theyhadbeenon1weplanetsformillionsofyearsbut2018wastheyearseveralspecies2officialdiedoffforever.Threebirdspecieswentextinctthisyeartwoof3aresongbirdsfromnortheasternBrazil.A4disturbtrendisthatmainlandspeciesarestartingtogoextinctratherthanislandspecies.Thespecies5wipeoutinthewildresultedfrommanyfactorssuchasthecreationofdamandtrapping6trade.Beyondbirdsotheranimalssuchasthevaquitaandthenorthernwhiterhino7beneartheend.Wearecurrentlyexperiencingtheworstspeciesdie﹣offssincethe81oseofthedinosaurs65millionyearsago.Althoughextinctionisa9naturephenomenonitoccursatarateofaboutonetofivespeciesperyear.Scientistsestimatewe'renowlosingspeciesat1000to10000timestherate.Inthepast500yearsabout1000species10goextinct.
一个样本容量为10的样本数据它们组成一个公差为2的等差数列{an}若a1a3a7成等比数列则此样本的平均数和中位数分别是
设集合A={x∈R|x＞2}B={x∈R|x2﹣3x≤0}则A∩B等于
如图在矩形ABCD中AB=2BC=1矩形ABEF是通过矩形ABCD以直线AB为轴旋转得到且BC⊥BE动点M在CD上． 1求证平面MBE⊥平面ABCD 2当M为CD的中点时求二面角B﹣EM﹣C的大小．
函数fx=2cosxsinxsin2x+sinxcosx在x∈[]的值域为．
Ifyoufollowtheseinsidertipsyourphotoswilllooklikeyouhadtheplacetoyourselfatthepopulartouristattractions.VaticanMuseums:VaticanCityTheVaticandrawsmorethanfivemillionpeopleeachyearandqueuescanreachfourhoursduringpeakseason.ChristieHudsonseniorcommunicationsmanageratExpediarecommendschoosingaskip﹣the﹣1inetour.'Thisnotonlyletsyouavoidtheticketcounterbutalsoincludestheuseofaprivatepartnerentrance.'ExtratimetovisittheSistineChapel?Yes!BambooForest:KyotoJapanBambooForestisthemostworthysightinKyoto.Ⅱyou'relongingtoenjoythepathwaysandtakepicturesintotalquietnessKyotoArashiyamaTravelGuiderecommendshittingthefamousBambooGrovePathasearlyinthemorningaspossible﹣think7a.m.ifyou'reupforit.Don'tmissthesehiddentreasuresyoucanonlywitnessinJapan.ChichenItza:YucatánMexicoHometoE1CastilloandtheTempleoftheWarriorsChichenItzaisamust﹣see.Wanttobeattherush?Scheduleanearlytourthattakesplacebeforeasiteopenstothepublic.Ledbyanarchaeologistguideit'sfulloffascinatinginsightsandfacts﹣withouttonsofpack﹣wearingtourists.LouvreMuseum:ParisFranceTheLouvreisoneofthemostpopularmuseumsontheplanet.Ifwaitingaroundinlinetogetinisn'tthewayyouprefertospendyourtimeinParisconsiderpurchasingareservedticket.Thiswillgiveyouentrytothepyramidwithinahalf﹣hourwindow.TheLouvreisalsoopenuntil9:45p.m.onWednesdaysandFridaysifyou'reupforsomelate﹣nightartvisits.1WhatisrecommendedatVaticanMuseumsbyChristieHudson?A.Queuingfourhours.B.Jumpingthewaitingline.C.Takingaskip﹣the﹣linetour.D.VisitingtheSistineChapel.2Whichofthefollowingareavailableforearlytouriststoavoidtherush?A.VaticanMuseumsandBambooForest.B.ChichenItzaandBambooForest.C.BambooForestandLouvreMuseum.D.ChichenItzaandLouvreMuseum.3Whomightthispassagebeintendedfor?A.Visitorsinterestedinmuseums.B.Guidesatthetouristattractions.C.Peopleattheticketcounter.D.Touriststobeattherush.
在△ABC中=E为AC中点CD与BE交点为F过点F的直线1分别交线段ABAC于点MN．若═λ=μ则λ+μ的最小值为．
已知函数fx=+ax+3gx=x3若∀mn∈[]fm﹣gn≥0则实数a的取值范围为
已知函数fx＝2sinωx﹣ω＞0和gx＝3cos2x+φ+1|φ|＜的图象的对称轴完全相同则下列关于gx的说法正确的是
假如你是校英文报编辑李华.你校原定于本星期五下午在302室举办的英文经典片段配音比赛EnglishDubbingContest因故需更改时间和地点.请你写一封电子邮件通知评委中的外教Mrs.Jenkins内容包括: 1.比赛更改原因; 2.更改后的安排; 3.表达歉意. 注意:1.词数100左右; 2.可以适当增加细节以使行文连贯.
已知椭圆C+=1a＞b＞0过点A01且椭圆的离心率为．Ⅰ求椭圆C的方程Ⅱ斜率为1的直线l交椭圆C于Mx1y1Nx2y2两点且x1＞x2．若直线x=3上存在点P使得△PMN是以∠PMN为顶角的等腰直角三角形求直线l的方程．
数列{an}是等差数列{bn}是各项均为正数的等比数列公比q＞1且a5=b5则
Theworldisagreenerplacethanitwas20yearsago.Astudypublishedinthejournal'NatureSustainability'saidthatrecentsatellitedatarevealsagreeningpatternthatisstrikinglyprominentinChinaandIndia.ThestudyshowsthathumanactivityinChinaandIndiadominatesthisgreeningoftheplanetthankstotreeplantingandagriculture.Theeffectcomesmostlyfromambitioustree﹣plantingprogramsinChinaandintensiveagricultureinbothcountries.'ChinaandIndiaaccountforone﹣thirdofthegreening'saidleadauthorChiChenofBostonUniversity.'Thatisasurprisingfindingconsideringthevagueideaoflanddegradation毁坏inpopulouscountriesfromoverexploitation'addedChen.Chinaaloneaccountsfor25percentoftheglobalnetincreaseinleafareawithonly6.6percentofglobalvegetatedarea.ThegreeninginChinaisfromforests42percentandcroplands32percentbutinIndiaitismostlyfromcroplands82percentwithminorcontributionfromforests4.4percent.China'soutsizedcontributiontotheglobalgreeningtrendcomesinlargepartfromitsprogramstoconserveandexpandforestswiththegoalofpreventinglanddegradationairpollutionandclimatechange.'Oncepeoplerealizethereisaproblemtheytendtofixit'saidRamaNemaniresearchscientistandco﹣authorofthestudy.'Inthe1970sand80sinIndiaandChinathesituationaroundvegetationlosswasnotgood.Inthe1990speoplerealizeditandtodaythingshaveimproved.Nowweseethathumansarecontributing.'LandareausedtogrowcropsiscomparableinChinaandIndia﹣morethan770000squaremiles﹣andhasnotchangedmuchsincetheearly2000s.Yettheseregionshavegreatlyincreasedboththeirannualtotalgreenleafareaandtheirfoodproduction.Thiswasachievedthroughmultiplecroppingpracticeswhereafieldisreplantedtoproduceanotherharvestseveraltimesayear.Productionofgrainsvegetablesfruitsandmorehaveincreasedbyabout35%～40%since2000tofeedtheirlargepopulations.1Whatdidthestudymainlyfind?A.IndiaandChinaareleadingtheglobalgreeningeffort.B.Intensiveagricultureisthecauseofgloballanddegradation.C.ChinaandIndiahasgotthelargestforestcoverageintheworld.D.Agricultureismorehelpfulinexpandinggreenareasthantree﹣planting.2HowisChinadifferentfromIndiaincontributingtotheglobalgreening?A.Indiareducedcroplandtopreventtheoverexploitation.B.Indiaincreasedforestbyplantingaroundcroplands.C.Chinachangedmorelandsintoforestbyplantingtrees.D.Chinacontrolledtheincreaseofitspopulation.3WhatdoesNemanithinkabouthumansinChinaandIndiainprotectingtheEarth?A.Ambitious.B.Responsible.C.Passionate.D.Tolerant.4Whatdoesthepassagefinallysuggesthumansshouldmakegooduseof?A.Forest.B.Trees.C.Cropland.D.Food
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. Ibecameinterestinginplayingfootballthankstoasmallaccident.OneafternoonwhereIwasinprimaryschoolIwaswalkingbytheschoolplayground.Suddenlyfootballfelljustinfrontofmebutalmosthitme.Istoppedtheballandkickedithardlybacktotheplayground.Toeveryone′ssurprisingtheballwentintothenet.AllthefootballplayerontheplaygroundcheeredloudlysaythatIhadatalentforfootball.FromnowonIstartedtoplaymyfootballwithclassmatesafterschool.Iamagoodplayernow.
热门题库
更多
高一下学期物理
高三下学期数学
高三上学期数学
高一下学期英语
教案备课库
高一上学期生物
高一下学期生物
高二上学期数学
高二上学期物理
高二上学期英语
高二上学期生物
高二下学期数学
高二上学期化学
高二下学期物理
高三下学期物理
高三上学期物理
湘公网安备 43130202000226号