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如图，在正四棱锥S﹣ABCD中，E，M，N分别是BC，CD，SC的中点，动点P在线段MN上运动时，下列四个结论中恒成立的个数为（ ） （1）EP⊥AC； （2）EP∥BD； （3）EP∥面...
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如图四棱锥P﹣ABCD中AB∥CDAB⊥ADBC=CD=2AB=2△PAD是等边三角形MN分别为BC
如图在四棱锥P—ABCD中底面ABCD是正方形PA⊥底面ABCD且PA=ABM.N.分别是PABC的
如图在四棱锥P-ABCD中底面ABCD是矩形PA⊥平面ABCDAP=ABBP=BC=2E.F.分别是
如图在四棱锥PABCD中PC⊥平面PADAB∥CDCD＝2AB＝2BCM.N.分别是棱PACD的中点
如图所示在正四棱锥S﹣ABCD中EMN分别是BCCDSC的中点动点P在线段MN上运动时下列结论中不
EP∥BD
EP∥面SBD
EP⊥AC
EP与SD异面
已知四棱锥S﹣ABCD的底面ABCD是直角梯形AB∥CDBC⊥AB侧面SAB为正三角形AB=BC=4
在三棱锥ABCD中E.F.G.H.分别是边ABACCDBD的中点且AD＝BC那么四边形EFGH是__
如图已知正四棱锥V.﹣ABCD中AC与BD交于点M.VM是棱锥的高若AC=6cmVC=5cm.1求正
在正三棱锥S.―ABC中M.N.分别是SCBC的中点且MN⊥AM若侧棱则正三棱锥S.―ABC外接球的
12π
32π
36π
48π
如图在四棱锥P-ABCD中底面为直角梯形AD∥BC∠BAD=90°PA⊥底面ABCD且PA＝AD=A
如图已知棱锥S.－ABCD底面为正方形SA⊥底面ABCDAB＝AS＝aM.N.分别为ABSC的中点.
如图在梯形ABCD中AD∥BCM.N.分别是ABCD的中点ME∥AN交BC于点E.求证AM＝NE.
如图在四棱锥P.－ABCD中PD⊥面ABCDAD∥BCCD=13AB=12BC=10AD＝12BC.
如图在四棱锥P.—ABCD中底面ABCD是矩形PA⊥平面ABCDAP=ABBP=BC=2E.F.分别
在正三棱锥S.―ABC中M.N.分别是SCBC的中点且MN⊥AM若侧棱则正三棱锥S.―ABC外接球的
12π
32π
36π
48π
如图在矩形ABCD中M.N.分别是边ADBC的中点E.F.分别是线段BMCM的中点若AB=8AD=1
如图在四棱锥P-ABCD中底面ABCD是矩形MN分别是ABPC的中点求证:MN∥平面PAD.
如图在四棱锥P.－ABCD中AB⊥ACAB⊥PAAB∥CDAB＝2CDE.F.G.M.N.分别为PB
如图四棱锥P.－ABCD中AB⊥ACAB⊥PAAB∥CDAB＝2CDE.F.G.M.N.分别为PBA
如图在四棱锥P.﹣ABCD中底面ABCD是正方形PA⊥底面ABCD垂足为点A.PA=AB=2点M.N
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在正方体ABCD﹣A1B1C1D1中E为棱CD上一点且CE＝2DEF为棱AA1的中点且平面BEF与DD1交于点G则B1G与平面ABCD所成角的正切值为
10分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短文.短文中共有10处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词符号∧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. WelcometotheGreatWall.Measuredmorethan6000kilometersinlengththeGreatWallisknownasthelongwallintheworld.Ithasalonghistoryofmorethan2000years.ThatisamazingabouttheGreatWallisthatitismainmadeofstonesandbricksandalltheconstructionwasdonebyhand.ThoughitwasusedtoprotectthecountryfromforeigninvaderseveryfewhundredmetersalongwiththeGreatWalltherewasawatchtower.NowassymbolofChinatheGreatWallhadbecomeoneofthemostfamoustouristattractionintheworld.ItisnowonderthattheGreatWallattracthundredsofthousandsofforeigntouristseveryyear.
10分假定英语课.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. WelcometotheGreatWall.Measuredmorethan6000kilometersinlengththeGreatWallisknownasthelongwallintheworld.Ithasalonghistoryofmorethan2000years.ThatisamazingabouttheGreatWallisthatitismainmadeofstonesandbricksandalltheconstructionwasdonebyhand.ThoughitwasusedtoprotectthecountryfromforeigninvaderseveryfewhundredmetersalongwiththeGreatWalltherewasawatchtower.NowassymbolofChinatheGreatWallwillbecomeoneofthemostfamoustouristattractionsintheworld.ItisnowonderfulthattheGreatWallattracthundredsofthousandsofforeigntouristseveryyear.
30分Stevewasaseventhgraderabigboylookingmorelikeateenagerthana12﹣year﹣old.Yethewentunnoticed﹣﹣hehadbeen1everyexaminationsincefirstgrade一untilMissWilma. Inthemiddleofthefirstsemesterofschooltheentireseventhgradewas2forbasicskills. YoualldidprettywellMissWilmatoldtheclassaftergoingoverthe3.exceptforoneboy.Andit4myhearttotellyouthisbut..she5thesmartestboyintheseventhgradeisfailingmyclass.Steve6hiseyesandcarefullyexaminedhisfingertips. AfterthatStevestillwouldn'tdohishomework.EvenifMissWilma7punishedhimheremained8 Steveplease!Icareaboutyou! 9Stevegotit!SomeoneCARESABOUTME?! OneMondayacoupleofweekslaterMissWilmagavea10ontheweekendhomework.Steve11throughthetestandwasthefirsttohandinhispaper.Withalookof12MissWilma1ookhispaperandbegantolookitover. MissWilma'sfacewasin13shock!SheglancedupatStevethen14then up.Thesmartestboyintheseventhgradehadjustpassedhisfirsttest! FromthatmomentnothingwasthesameforSteve.Hediscoveredthatnotonlycouldherememberandunderstand15buthecouldtranslatewhathelearnedintohislife.Hebecame16 AfterhighschoolSteveenlistedintheNavyandhehadan17militarycareer.Duringhisnavalyearsheinspiredmanyyoungpeoplewhomightnothave18themselveswithouthim. A19tookplacewithintheheartofaboyallbecauseofoneteacherwho20. 1A.missing B.failing C.passing D.skipping 2A.tested B.classified C.separated D.dismissed 3A.questions B.effects C.lessons D.results 4A.fills B.presses C.breaks D.destroys 5A.shouted B.hesitated C.interrupted D.laughed 6A.dropped Braised C.covered D.closed 7A.strangely B.steadily C.severely D.secretly 8A.helpless B.stubbom C.flexible D.crazy 9A.Commonly B.Unwillingly C.Particularly D.Suddenly 10A.quiz B.chance C.speech D.presentation 11A.slept B.looked C.lived D.hurried 12A.disppointment B.surprise C.satisfaction D.inspiration 13A.btter B.total C.precious D.ridiculous 14A.down B.away C.out D.back 15A.homework B.grades C.knowledge D.subjccts 16A.outstanding B.lazy C.rough D.troublesome 17A.tiring B.ordinary C.hardworking D.successful 18A.reliedon B.lookedafter C.turnedto D.believedin 19A.competition B.choice C.change D.campaign 20A.waited B.listened C.wished D.cared
10分ImagineachildstandingonadivingboardfourfeethighandaskinghimselfthequestionShouldIjump?Thisiswhatmotivationorthelackofitcando.Motivationandgoalsettingarethetwosidesofthesamecoin.1.Likethechildonthedivingboardyouwillstayundecided. 2.Morethanthathowshouldyoustaymotivatedtoachievethegoal?Firstyouneedtoevaluateyourselfyourvaluesyourstrengthsyourweaknessesyourachievementsyourdesiresetc.Onlythenshouldyousetyourgoals. Youalsoneedtojudgethequalityanddepthofyourmotivation.Thisisquiteimportantbecauseitisdirectlyrelatedtoyourcommitment.Therearetimeswhenyourheartisnotinyourwork.3.Soslowdownandthinkwhatyoureallywanttodoatthatmoment.Clarity清晰ofthoughtscanhelpyoumoveforward. Anotherwayofsettingrealisticgoalsistoanalyzeyourshortandlongtermobjectiveskeepinginmindyourbeliefsvaluesandstrengths.Rememberthatgoalsareflexible.4.Theyalsoneedtobemeasurable.Youmustkeepthesepointsinmindwhilesettingyourgoals. Yourpersonalcircumstancesareequallyimportant.Forexampleyoumaywanttobeapilotbutcan'tbecomeonebecauseyoureyesightisnotgoodenough.5.Youshouldreassessyourgoalsandmotivateyourselftosetafreshgoal. Youwillsurelyneedtoovercomesomedifficultiessomeplannedbutmostunplanned.Youcannotovercomethemwithoutamplemotivation.Makesurethatyouplanforthesedifficultiesatthetimeofsettingyourgoals. A.Thiscanaffectyourwork. B.Sohowshouldyoumotivateyourself? C.Howeverthisshouldnotdiscourageyou. D.Sowhyshouldwetrytosetspecificgoals? E.Theycanchangeaccordingtocircumstances. F.Motivationiswhatyouneedmosttodoagoodjob. G.Withoutmotivationyoucanneithersetagoalnorreachit.
已知双曲线的左右焦点分别为F1F2若双曲线的渐近线上存在点P使得|PF1|＝2|PF2|则双曲线C的离心率的取值范围是．
8分LOSANGELESNov.12Xinhua﹣LegendarycomicbookwriterStanLeehasdiedattheageof95accordingtomediareportsonMonday. LeeborninStanleyLieberonDec.281922beganhiscareerin1939andjoinedtheMarvelComicsin1961. HeisconsideredasoneofthemostlegendarynamesinthehistoryofcomicbooksandtheleadingcreativeforcebehindtheriseofMarvelComics.Heco﹣creatediconicfictionalcharacterssuchasSpider﹣ManX﹣MentheAvengersandmanymore. Lee'scharactersoftenhavesuperpowersbuttheyalsohaveweaknesses.Theywerehumansnotgods.Theynotonlystruggledtosavetheworldbutalsotopaytheirbillsmakefriendsandholdjobs.ThismadeMarvelcomicbookheroesstandapartfromitscompetitorDCwhichproducedtheseeminglyperfectheroeslikeSupermanandWonderWoman.ThosesuperheroeshavebeenadaptedintoblockbusterfilmsmostofwhichweremadeafterDisneyacquiredMarvelina4﹣billion﹣dollardealin2009. InastatementBobIgerchairmanandCEOoftheWaltDisneyCompanysaidStanLeewasasextraordinaryasthecharactershecreated. MarvelalsopraisedLeeonitswebsitebyputtingononeofLee'sfamousquoteswhichgoesIusedtobeembarrassedbecauseIwasjustacomic﹣bookwriterwhileotherpeoplewerebuildingbridgesorgoingontomedicalcareers.AndthenIbegantorealizeentertainmentisoneofthemostimportantthingsinpeople'slives.Withoutittheymightgooffthedeepend.Ifeelthatifyou'reabletoentertainyou'redoingagoodthing. PraisefromhisHollywoodpeersandcolleagueswasgenerous.PresidentofMarvelStudiosKevinFeigeappreciatedLee'sunparalleledimpactontheindustry.NoonehashadmoreofanimpactonmycareerthanStanLeeFeigesaid.OurthoughtsarewithhisfamilyandthemillionsoffanswhohavebeenforevertouchedbyStan'sgeniuscharismaandheart. 1HowdoLee'scharactersdifferfromthoseofDC? A.Theyareperfectheroes. B.Theyoftenhavesuperpowers. C.Theyarenothumansbutgods. D.Theyhavehumanshortcomings. 2WecanlearnfromLee'sstatementinParagraph6that. A.itisembarrassingtobeacomic﹣bookwriter B.atasteofentertainmentisnecessaryinpeople'slives C.entertainmentisthemostimportantthingintheworld D.youcandoeverythingwellifyouareabletoentertain 3Accordingtothepassagewecouldknowthat. A.LeeinfluencedKevinFeige'scareeralot B.LeejoinedtheMarvelComicsinhisforties C.Leecreatedthefictionalcharactersallbyhimself D.ThesuperheroeswereadaptedintofilmsbeforeDisneyacquiredMarvel 4Whatcanbethebesttitleforthepassage? A.ComicsLegend﹣theMarvelsandDC B.TheSuperheroesinStanLee'sComics C.Marvel'sComicsLegendStanLeeDiesat95 D.TheLifeStoryofMarvelComicsLegendStanLee
已知函数fx＝|x+2a|a∈R． 1当a＝1时解不等式fx+|x﹣a|≤5 2若fx+|x﹣1|≤2的解集包含[12]求a的取值范围．
Thehottestcitiesintheworld Thelocationsbelowarethehottestandalsotraveldestinationsontheplanet. Bangkok AccordingtothedataBangkokisthehottestcityontheplanet﹣notbecauseofanyparticularlyimpressivehightemperaturesbutbecauseitisconsistentlyhotalltheyearround.Thecityhasanaverageannualtemperatureof29℃coupledwithhighdampnessandanaverageof128rainydaysperyearwhilethehighesttemperatureonrecordis40℃. TimbuktuMali LocatedonthesouthernedgeoftheSaharaDeserttheAfricancityofTimbuktuissimilartoeverythingremote.It'salsooneofthehottestcitiesintheworldwithahotdryclimateofferingrecordhighsof49℃.ThroughoutAprilMayandJuneaveragemaximumtemperaturesarebeyond40℃.Modern﹣dayTimbuktuisslowlybeingswallowedbythedesertandiscertainlyashadowofthetradecenterthatitoncewas. AhvazIran BuiltonthebankoftheKarunRiverAhvazisanindustrialcitywithaveragehighsofaround46℃duringJulyitswarmestmonth.Thecity'srecordhighis54℃makingitoneoftheworld'shottestcitiesduringthesummer.FrequentsandandduststormsandanabsenceofrainfromJulytoSeptembermixwithitssky﹣hightemperatures. KuwaitCity ThewealthycapitalofKuwaitisanothercompetitorforthetitleoftheworld'shottestsummertimecitywithaveragehighsofover45℃fromJunetoAugust.Nightfallbringslittlerespite缓解withafter﹣darklowtemperaturesoftenover30℃duringthesummermonths.KuwaitCity'srecordhighis52℃whileitrainsonanaverageofjust19daysperyear. 1WhatistheBangkokfamousforinclimate? A.Thehighesttemperature. B.Thehotweatherallyearround. C.Thehighestannualtemperature. D.Thelackofrainfallallyearround. 2WhyisTimbuktunolongeratradecenter? A.ThesmallpopulationofMali. B.Thewarlastingformanyyears. C.TheinfluenceoftheSahara. D.Itslocationofthecenterofadesert. 3Whichcityholdstherecordofthehighesttemperature? A.Ahvaz. B.Bangkok. C.Timbuktu. D.KuwaitCity.
WhenshefirststartedlearningabouttheclimatechangefromoneofhereldersFawnSharpwasinvitedonahelicopterflightovertheOlympicMountainstosurveytheMountAndersonglacier冰川.Buttheglacierwasgonemeltedbythewarmingclimate.Sharphadadeepsenseoflosswhenshediscoveredtheglacierwasn'tthereanymore. Lossisagrowingissueforpeopleworkingandlivingonthefrontlinesofclimatechange.AndthatgaveJenniferWrenAtkinsonafll﹣timelecturerattheUniversityofWashingtonBothellUSanideaforaclass. ThistermshetaughtstudentsontheBothellcampusaboulthecmotionalburdensofenvironmentalstudy.SheusedtheexperiencesofNaliveAmericantribes部落scientistsandactivistsandaskedher24studentstofacetherealitythatthereisnoeasyfix﹣﹣thatthisissuchanintractableproblemthatthey'regoingtobedealingwithitfortherestoftheirlives. StudentCodyDillonusedtobeaclimatescienceskeptic怀疑论者.Thenhedidhisownreadingandresearchandchangedhismind. Dillonwasn'tgoingintoenvironmentalwork﹣﹣hewasacomputer﹣sciencemajor.Yetthepotentialforaworldwideenvironmentalcatastropheseemedsorealtohimfiveyearsagothathequithisjobandbecameafll﹣imevolunteerforanenvironmentalgroupthatworkedonrestoration恢复projects. SixmonthsintotheworkhedecidedthatAlkinson'sclasswasjustwhathewaslookingfor﹣﹣aplacewherehecoulddiscusshisconcernsaboutachangingclimate. Atkinsonsaidshehopestheclasshelpedherstudentspreparethemselvesfortheamountofenvironmentallossthatwillhappenovertheirlifetimes. Wearealreadychangingtheplanet﹣.somanyspeciesaregoingtobelostdisplacedormassivelyimpacted巨大影响的shesaid.Thefutureisn'tgoingtobewhattheyimagined. 1WhydidtheauthormentionthecaseofFawnSharp? A.TolayabasisforFawnSharp'sfurtherresearch. B.ToproveFawnSharp'sworkissimilartoAtkinson's. C.Toleadintotheissueoflosscausedbyclimatechange. D.Toshowscientists'concernabouttheMountAndersonglacier. 2What'sthemainpurposeofAtkinson'sclass? A.Toexplorehowdifferentpeopledealwithclimatechange. B.Togetstudentsmoreconcernedaboutenvironmentalissue. C.TofindsolutinstotheOlympicMountainsenvironmentalissue. D.Toteachstudentshowtoconductaresearchaboutenvironment. 3WhichofthefollowingbestexlainsintractableunderlinedinParagraphThree? A.Simple. B.Difficult. C.Common. D.Interesting. 4HowdidAtkinson'sclassinfluenceDillon? A.Dillonworkedasapart﹣timevolunteerforrestorationprojects. B.Itmadehimrealizeaplanet﹣wideclimatedisasterwouldhappen. C.Itencouragedhimtobemoreinvolvedinenvironmentalprotection. D.Itdiscouragedhimtoworkonrestorationprojectsfortheenvironment.
已知某几何体是由一个三棱柱和一个三棱锥组合而成的其三视图如图所示则该几何体的表面积为
30分 AGoodMan It'salateSaturdayafternooninearlyMarchandIamsweatinginsearchoftheonlygiftmysonwantsfromLosAngelesa1tothehomesofthestarssuchasBradPittandJetLi. AcheerfultaxidriversaysNoproblem.Mapsellersareeverywhere!Whenthetaxistopsafellow2withathinfoldedsheetandsaysTendollars. Tendollars!Withabsolute3IinformhimThat'stoomuch.Themapmanleaves.IbeginwalkingcertainI'llfindaan4starmapsoon. Iam5.There'shardlyanybodyonthestreet.Theredon'tseemtobemanyrealstoresjustcarsandbars.Nomaps.Nostars.Blockspass.Thesunbeginstosink.AttheedgeofWestHollywood6fellowwandersaheadsellingstarmapstosometeenagegirls. Tendollars7.Forgetit.Mysonwill8. ThatnightIcallmywife.Didyougetoneofthosemapstothestars?He'sbeentalkingabout9else. This10ishardtoignore.It'slate.Atall﹣nightmarketsnomaps.Iheadbacktothehotel.Morningiscoming.Therewillbeonelast11.AfterIcheckoutItakeataxi.Butatnineinthemorningmapsellersare12tobefound. YouknowsaysthedriverTheguyswiththemapsjustaren'tupyet!He'sright. Forgetit.Let'sgototheairport. WellsaysthedriverIcould13youoneifyoulike. Sure.Trustthisguy?Imightaswellthrowcashontothefreeway.ButexitingthetaxiI14mylastchance.Ihandhim﹩13andmybusinesscard.Threeweekspass.I've15onthestarmap.Mysonhasstoppedmentioningit. Thenoneafternoonstickingoutfromunderpilesofflyersthereitisabigwhiteenvelope.Thereisasmallnote.Icanhardlyreadit16Imakeoutafewphrases﹣forgive17taxi'sbeendownandfinallyhere'smapforyourson.There'snoreturnaddress.It'ssignedkindregardsM. Iholdthenoteinmyhand18whatmysonsaidtomewhenIgotbackfromLosAngeles. Didyoumeetany19Dad?heasked. NowIknowwhattotellhim. YesIdid.ImetaguynamedM. Ifyounever20anybodyyou'llneverfindthegoodguys. 1A.decoration B.map C.book D.symbol 2A.argues B.requests C.competes D.approaches 3A.assurance B.permission C.anxiety D.bargain 4A.perfect B.inexpensive C.proper D.detailed 5A.shocked B.confused C.impatient D.wrong 6A.any B.some C.another D.either 7A.still B.even C.almost D.yet 8A.believe B.regret C.understand D.admit 9A.anything B.everything C.something D.nothing 10A.idea B.news C.change D.reason 11A.try B.journey C.action D.minute 12A.everywhere B.somewhere C.anywhere D.nowhere 13A.give B.mail C.show D.spare 14A.create B.recognize C.deserve D.blow 15A.givenup B.throwndoubts C.refusedoffers D.droppedin 16A.and B.or C.but D.for 17A.fault B.delay C.carelessness D.rudeness 18A.remembering B.reminding C.reviewing D.realizing 19A.admirers B.friends C.stars D.heroes 20A.lookupto B.turnto C.havefaithin D.agreewith
25分假定你是李华想邀请热心于公益的留学生朋友Bryan一起去你市火车站参加为期两天的志愿服务活动.请给他写封邮件内容包括 1.活动时间地点 2.志愿服务内容至少三个方面. 注意 1.词数100左右 2.可以适当增加细节以使行文连贯. DearBryan Sincerelyyours LiHua
已知||＝2||＝3的夹角为120°则|2+|＝．
15分OnOctober232018PresidentXiJinpingannouncedtheopeningoftheHongKong﹣Zhuhai﹣MacaoBridgeHZMBatanopeningceremonyinZhuhaiGuangdongprovince. TheHZMB1locateatthewatersoftheLingdingyangofPearlRiverEstuaryisahugeseacrossinglinkingHongKongandMacaototheChinesemainlandcityofZhuhai.Astheworld's2longsea﹣basedprojectthe55﹣kilometrebridgeistheresultoffiveyearsofresearchandanothernineyearsofbuilding.Ithasbeendescribedasoneoftheseven3wonderofthemodernworldbytheGuardian. Theproject4makeupofa22.9﹣kilometer﹣longmainbridgea6.7﹣kilometer﹣longtunnelandanartificialislandoffthebridge.Itisdesignedwith5servicelifeof120years.Itcanwithstandastrongwindequal6amaximumBeaufortscale16.Thebridge'sengineershadtoconsidermanyenvironmentalfactorstoprotectthe7surroundenvironmentwhilebuildingthebridge.Chinesewhitedolphinsanendangeredspeciesthatlivesinthearea8beaparticularconcern. TheHZMBwillmake9muchmoreconvenienttotravelbetweenthethreeareasitconnects.ItwillbringpeopleinHongKongMacaoandGuangdongwithinaone﹣hourlivingcircle10isexpectedtoattractmorevisitorstotheGuangdong﹣HongKong﹣MacaoGreaterBayArea.Itwillbeatransportlinkaswellasasocialeconomicculturalandtourismconnectionamongthethreeareas.
已知等差数列{an}的前n项和为Sna3+a5＝18S3+S5＝50．数列{bn}为等比数列且b1＝a13b2＝a1a4． 1求数列{an}和{bn}的通项公式 2记其前n项和Tn证明．
8分MarianBechtelsitsatWestPalmBeach'sBarLouiecounterbyherselfquietlyreadinghere﹣bookasshewaitsforhersalad.Whatisshereading?Noneofyourbusiness!LunchisBechtel'smetime.AndlikemoreAmericansshe'snotalone. Anewreportfound46percentofmealsareeatenaloneinAmerica.Morethanhalf53percenthavebreakfastaloneandnearlyhalf46percenthavelunchbythemselves.Onlyatdinnertimeareweeatingtogetheranymore74percentaccordingtostatisticsfromthereport. Iprefertogooutandbeout.Alonebuttogetheryouknow?Bechtelsaidlookingupfromherbook.BechtelwhoworksindowntownWestPalmBeachhaslunchwithcoworkerssometimesbutlikemanyofustoooftenworksthroughlunchatherdesk.Alunchtimeescapeallowshertokeepabossfromtappingherontheshoulder.Sheretunstoworkfeelingenergized.TodayIjustwantedsometimetomyselfshesaid. JusttwoseatsoverAndrewMazolenyalocalvideographerisfinishinghislunchatthebar.Helikesthathecansitandcheckhisphoneinpeaceorchatupthebarkeeperwithwhomhe'sonafirst﹣namebasisifhewantstohavealittleinteraction交流.Ireflectonhowmyday'sgoneandthinkabouttherestoftheweekhesaidIt'sachanceforself﹣reflection.Youreturntoworkrechargedandwithaplan. Thatfreedomtochooseisonereasonmorepeopleliketoeatalone.Therewasatimewhenpeoplemayhavefeltawkwardaboutaskingforatableforonebutthosedaysareover.Nowwehaveoursmartphonestokeepuscompanyatthetable.Itdoesn'tfeelasaloneasitmayhavebeforealltheadvancesintechnologysaidLaurieDemerittwhosecompanyprovidedthestatisticsforthereport. 1Whatarethestatisticsinparagraph2about? A.Foodvariety. B.Eatinghabits. C.Tablemanners. D.Restaurantservice. 2WhydoesBechtelprefertogooutforlunch? A.Tomeetwithhercoworkers. B.Tocatchupwithherwork. C.Tohavesometimeonherown. D.Tocollectdataforherreport. 3WhatdoweknowaboutMazoleny? A.Hemakesvideosforthebar. B.He'sfondofthefoodatthebar. C.Heinterviewscustomersatthebar. D.He'sfamiliarwiththebarkeeper. 4Whatisthetextmainlyabout? A.Thetrendofhavingmealsalone. B.Theimportanceofself﹣reflection. C.Thestressfromworkingovertime. D.Theadvantageofwirelesstechnology.
若x＝1是函数fx＝x3+x2+ax+1的极值点则曲线y＝fx在点0f0处的切线的斜率为
25分假定你是校排球队队长李华.请写封邮件告知你的队友Chris球队近期将参加比赛内容包括 1.比赛信息 2.赛前准备 3.表达期待. 注意 1.词数100左右 2.可以适当增加细节以使行文连贯.
七巧板是我国古代劳动人民的发明之一被誉为“东方模板”它是由五块等腰直角三角形一块正方形和一块平行四边形共七块板组成的．如图所示的是一个用七巧板拼成的正方形若在此正方形中任取一点则此点取自黑色部分的概率为
已知函数fx＝xlnx﹣kx2﹣xab是函数x的两个极值点a＜b． 1求k的取值范围 2证明a•b＞e2．
6分KendickLamarhasn'thadmuchluckwhenitcomesiowningaGramy.Butthat'sOKTheUSrapper说唱歌手hasjustwonaPulitzerPrizeforhismusic. In2014in2016andagainthisyear.Lamarwasnominated提名foranalbumoftheyearGrammy.EachtimehewasbeatenoutfirstbyTaylorSwiftnextbyDaftPunkandmostrecentlybyBrunoMars. ButthePulitzePrizecommitteewasispiredcnoughbyLamar's2017albumDamn.toawardthe30﹣year﹣olditsPulizerPrizeinmusiconApril16.It'sanamazingalbumthatdocumentsthereallifeofmodemAfrican﹣AmericansinSouthLosAngeleswithwildlyaccomplishedbeatsandrhythms. Lamar'swinisconsideredtobehistorical.'ThePulizershavelongdisplayedtheirpreferencetowardhighartratherthanthepopcultureofthemasses.Soit'snotjustthatnorapperhaseverwonaPulitzernopopmusicmakerhaseverwononeintheaward's75﹣yearhistory. ButLamarisnotjustasinger一he'scleveratusinglanguage.Likethebestwritershismusicdescribessmallmomentsthatilustrate阐明largerpoints.HissongsareabouthisexperienceasablackmanwhogrewupinCalifomiastruggledgotintotroubleandfoundhiswayoutbyworkinghardandmakingsenseofthehistoryandrealityofracialproblemsintheUS. He'sanartistwhochallengesideasaidRyanCooglerdirectoreoftheblockbuste大片hitBlackPantherforwhichLamarcreatedmusic.Onebigthemeinourfimisthisideaof'WhatdoesitmeantobeAfrican?'Kendrickinhismusicisveryexactlyanddirectlychallengingthatquestion. Goodartistsentertainusgreataristsmakeusthinkandexceptionalaristshelpusempahize感同身受.Therearealotofgoodgreatevenexceptionalartistsinrockpopcountryandhip﹣hop.ButonlyLamarhasaPulizterPrize. 1WhatisLamarsalbumDamnabout? A.African﹣Americans'historyandculture. B.HardshipsoftheAfrican﹣Americanartists. C.ThewaystheUSgovemmentdealwithracialproblems. D.ThelivesofmodemblackpeopleinSouthLosAngeles. 2WhyisLamar'sPulitzerPrizewinsignificant? A.Heisthefirstfilm﹣makertowintheprize. B.Itisconsideredamilestoneforpopmusic. C.Heisthefirstblackpersontowintheprize. D.HehasmissedGrammyseveraltimesbefore. 3WhatcanwelearnfromRyanCoogler'swords? A.Lamardrewinspirationfromhisownexperience. B.Lamarhasthecouragetotakeonbigcallengesinlife. C.BlackPantheriswellknownbecauseofLamar'smusic. D.Lamar'smusicmathesthethemeofBlackPantherwell.
Iamtravelinghome.Itisbitterlycoldandsnowybutthewarmtrainisrightontime.IfeelpleasantlysatisfiedasIlookoutattherushhourtrafficonthemotorway.Ifeelmoresatisfiedasthesmelloffreshcoffeeannouncesthearrivalofthedrinksservice.SwissfriendsoftentellmeproudlythattheirrailserviceisthebestintheworldbutrecentlyoneexperiencehasprovedthatthegreatSwissloveaffairwiththeirrailwayhasturnedalittlesour. Itallbeganwiththedecisiontoendticketsalesontrains.OnecoldmorningIarrivedatmylocalstationonlytofindthattheticketmachinewasbroken.NomatterIthoughtIhavegotasmartphoneandIhurriedlysetaboutbuyingmyticketthatway.ThiswasnotaseasyasIhadexpectedbusyingmyselfbetweencreditcardandphonewithfreezingcoldfingersbutbythetimeIgotonthetraintoGenevaIhadane﹣ticketandIproudlyshowedittotheconductor.Unfortunatelyshetoldmethatmyticketwasnotvalid有效的.SeveralweekslateraletterarrivedfromSwissrailwaystogetherwithafinefor190francs﹩210. Thegoodpeopletheretellmetheformalpaymentformyticketfrommycreditcardcompanyarrivedfourminutesaftermytrainleftthestation.ThatmeanstheysaythatIboughtmyticketonthetrain﹣andthatisstrictlyprohibited. Swissrailwayssaytheirpolicyisdesignedtoprotecthonestticket﹣payingpassengersbutaquicklookattheirbalancesheetsuggestssomethingelse.Thecompanyismakingabout﹩2millionamonthfromfines. Althoughtraintravelisstillpopularthoseseatsdonotfeelascomfortablethecoffeedoesnotsmellquitesogood﹣becauseSwissrailwayshavelostfornowanywaysomethingfarmorepreciousthan﹩2millionamonthgoodrelationswiththeircustomers. 1Whatcanwelearnfromparagraph1? A.TheSwisstrainsusuallycomelate. B.Trafficonthemotorwaygoessmoothly. C.TheauthorhatestravelingontheSwisstrain. D.TheauthorisgenerallypleasedwiththeSwissrailservice. 2Whydidtheconductorsaythattheauthor'se﹣ticketwasinvalid? A.Itwaspurchasedonline. B.Itwaspaidforafterthetrain'sdeparture. C.Itwaspurchasedonaticketmachine. D.Itwaspaidonasmartphone. 3Whatdoestheauthorwanttoshowbytellingtheexperience? A.Thefinewasunfair. B.Theconductorwasimpolite. C.E﹣ticketsaregettingpopular. D.Creditcardscanbeinconvenient. 4WhatdoestheauthorthinkofthenewpolicyofSwissrailways? A.Itattractsmorepeopletotravelbytrain. B.Itmakesthecompanylosealotofmoney. C.Itdamagescompany﹣customerrelations. D.Itprotectshonestticket﹣payingpassengers.
Your2018ReadingListProvidedbyBillGates Mostofuscan'tlivelikebillionaireMicrosoftco﹣founderBillGatesbutwecanreadlikehim.Gatesrecommendedfourbooksin2018﹣thoughsomewerepublishedearlier. LeonardodaVincibyWalterIsaacson2017 ThebestsellingbiographerofSteveJobsandAlbertEinsteinresearcheddeeplyintodaVinci'scontributionsbeyondarthighlightingthebreadthofhisscientifictechnologicalandcreativeoutput.Leonardonearlyunderstoodalmostallofwhatwasknownontheplanetatthetime.That'smostlybecauseofhiscuriosityabouteveryareaofnaturalscienceandthehumanexperiencesaidGates. TheBestWeCouldDoAnIllustratedMemoirbyThiBui2017 Gatescallsthisgraphicnovelreallyimpressive.BuiisthedaughterofVietnameserefugeeswhocametoAmericaafterthefallofSaigonandbecomingaparentinspiredhertolookintoherownparents'miserablehistory.IwasstruckbyhowtheexperiencesBuiillustratesmanagetobebothuniversalandspecifictotheircircumstancessaidGates. LincolnintheBardobyGeorgeSaunders2018 Saundersalong﹣timeshortstorywriterwonhighpraiseforthisnovel.Thebookimaginestheghoststhathaunt萦绕thebasementofWillieLincolnAbrahamLincoln'ssonwhodiedat11inreallife.Willie'sdeathaftertheCivilWarmadethepresidenthaveanewunderstandingofthegriefhe'screatinginotherfamiliesbysendingtheirsonsofftodieinbattlesaidGates. OriginStoryABigHistoryofEverythingbyDavidChristian2018 ThisnewbookisbythecreatorofBigHistoryafreeonlinesocialstudiescourse.IttraceshistoryinwidesweepingmovementsstartingwiththeBigBanganditprovidesineffectashortcourseinmodernscience.Thisisabriefhistoryoftheuniverse.DavidgetsalittlestuckonthecurrenteconomicandpoliticalproblemsintheWestandIwishhetalkedmoreabouttheroleinnovationwillplayinpreventingtheworsteffectsofclimatechangesaidGates. 1Whichbooksrefertothefieldofscience? A.OriginStoryandLeonardodaVinci B.LincolnintheBardoandOriginStory C.LeonardodaVinciandTheBestWeCouldDo D.TheBestWeCouldDoandLincolnintheBardo 2Ifyouareinterestedinthrillerswhosebookwillyoumostprobablychoose? A.WalterIsaacson B.ThiBui C.GeorgeSaunders D.DavidChristian 3WhichofthefollowingstatementsisTRUE? A.TheBestWeCouldDoisanautobiography. B.LincolnintheBardohasbeenwarmlyreceived. C.DavidChristiantalksmuchaboutthepartthatinnovationwillplay. D.ReaderscanonlyreadaboutLeonardodaVinci'scontributionstowardsart.
10分Ifonethingonyourwish﹣listisastress﹣freeholidaythenherearesomeshoppingtipspreparedforyouwhichwillsavebothyourtimeandmoney. Don'tbetoughonyourbrains.1Don'tbeafraidtolookforcluesandaskforideas.Firstseewhetherthefolksonyourto﹣buy﹣forlisthavealreadydroppedsomevaluablehintsoftheirdreameditems.Ifyoustrikeoutencourageyourluckyrecipientstopostitemstheywishsomeonewouldbuyforthem.Youcanalsofindinspirationinthemanyonlinegiftguides.2﹣GiftsforDadsGiftsforGolfersandsuch.Thenyou'llgettheidea. 3Youreallycanenlistyourownpersonalhelpers.Don'tfeelguiltyaboutthat﹣afterallSantaemployshelperstoo.Manystoreshavefreeprofessionalshopperswhocanpickoutpresentsforyou.We'renottalkingjusthigh﹣endstoressuchasBlooming﹣dale'sandNordstrom.4They'reallhungrytowinyourbusinessawayfromonlineretailers.Butyou'lllikelyneedanappointmentsocallaheadorsearchstores'websitesforpersonalshopping.You'lltypicallyfindalinkonthehomepageunderContactUsorServices. Havegiftsdelivered.Timeismoneyandfornotalotofmoneyyoucansavealotoftimebyhavingyourgiftsdeliveredrighttoyourdoor.Somemom﹣and﹣popshopsofferdeliveryservicewhilechainstorestendtochargeforthatbutitstillmightbeworthpayingfortheconvenience.5Firstgotopostmates.comordownloadthefreeappandseewhetherit'savailableinyourarea.Thentypethenameofastoreintothesearchbarclickonthestoreandentertheitemyouwant. A.Makeanappointmentahead. B.Can'tfigureoutwhattobuy? C.Doyouwishforastress﹣freeholiday? D.Getsomeoneelsetodoshoppingforyou. E.Theyaretypicallyorganizedbyrecipientinterestand/orpricerange. F.OtherslikeMacy'sandJ.Crewwillalsoletyouleavetheshoppingtothem. G.Forlocalstoresthatdon'tofferthisconveniencetrythePost﹣matesdeliveryservice.
已知复数z＝为纯虚数则实数a＝
Usingamobilephoneformorethan10yearsincreasestheriskofgettingbraincanceraccordingtothemostcomprehensivestudyoftherisksyetpublished. Thestudy﹣whichisdifferentfromofficialstatementsthatthereisnodangerofgettingthedisease﹣foundthatpeoplewhohavehadthephonesforadecadeormorearetwiceaslikelytogetamalignanttumour恶性肿瘤onthesideofthebrainwheretheyholdthehandset. Thescientistswhoconductedtheresearchsayusingamobileforjustanhoureveryworkingdayduringthatperiodisenoughtoincreasetherisk﹣andthattheinternationalstandardusedtoprotectusersfromtheradiationisnotsafeandneedstoberevised. Theyconcludedthatcaution警告isneededintheuseofmobilephonesandbelievechildrenshouldbediscouragedfromusingthematall. Britain'slargestinvestigationintothehealthrisksofthetechnologytheMobileTelecommunicationsandHealthResearchMTHRprogramme﹣foundedbygovernmentandindustrysources﹣reportedthatmobilephoneshavenotbeenfoundtobeassociatedwithanybiologicalorharmfulhealtheffects. ButitschairmanProfessorLawrieChallisadmittedthatonlyasmallpercentageoftheresearchhadcoveredpeoplewhohadusedthephonesformorethanadecade.HewarnedWecannotruleoutthepossibilityatthisstagethatcancercouldappearinafewyears'time. Thenewstudy﹣headedbytwoSwedesProfessorLennartHardelloftheUniversityHospitalinOrebroandProfessorKjellHanssonMildofUmeaUniversitywhoalsoservesontheMTHRprogramme'smanagementcommittee﹣goessomewaytomeetingthedeficiency缺陷. Thescientistspulledtogethertheresultsofthe11studiesthathavesofarinvestigatedtheoccurrenceoftumoursinpeoplewhohaveusedphonesformorethanadecadeusingresearchinSwedenDenmarkFinlandJapanGermanytheUnitedStatesandBritain.Theyfoundalmostallhaddiscoveredanincreasedriskespeciallyonthesideoftheheadwherepeoplelistenedtotheirhandsets. Fiveofthesixstudiesofmalignanttumourfoundanincreasedriskandonlyonedidnotstillfoundanincreaseinbenign良性的tumour.Fourofthefivestudiesthatlookedatacousticneuromas听神经肿瘤foundthem.Theexceptionwasbasedononlytwocasesofthediseasebutstillfoundthatlongtermusershadlargertumoursthanotherpeople. Thescientistsputthefindingsofallthestudiestogethertoanalysethem.Thisshowedthatpeoplewhohaveusedtheirphonesforadecadeormoreare20percentmorelikelytocontractacousticneuromasand30percentmorelikelytogetmalignantgliomas胶质瘤. Theriskisevengreateronthesideoftheheadthehandsetisusedlongtermusersweretwiceaslikelytogetthegliomasandtwoandahalftimesmorelikelytogettheacousticneuromastherethanotherpeople. ThescientistsconcludeResultsfrompresentstudiesonuseofmobilephonesformorethan10yearsgiveaconsistentpatternofanincreasedriskforacousticneuromaandglioma.Theyaddthatanincreasedriskforothertypesofbraintumourscannotberuledout. 1ThenewstudyheadedbythetwoSwedes. A.correctedtheabsenceintheMTHRprogramme'smanagement B.cametoaconclusionsimilartothatofMTHR'sinvestigation C.ruledoutthepossibilitythatlongtimeuserscouldgetbraincancer D.madesomeimprovementsbyexpandingtheinvestigationsamples 2Thepassagetriestotellusthat. A.usingmobilephonesisdangeroustopeople'shealth B.childrenshouldbeforbiddentousemobilephones C.peopleusingmobilephonesanhoureveryworkingdaywillgetbraincancer D.themorepeopleusemobilephonesthemorelikelytheyaretogetbraincancer 3TheunderlinedwordcontractinParagraph10probablymeans. A.beinfectedwith B.beassociatedwith C.befacedwith D.becoveredwith 4Thebesttitleofthepassageis. A.TheCausesofBrainCancer B.TheHiddenDangerofMobilePhones C.TheResearchofBrainCancer D.TheEffectsofMobilePhones
若函数fx＝m+sinx﹣cosx的最大值为0则m＝
15分A90﹣year﹣oldhasbeenawardedWomanOfTheYearfor1beBritain'soldestfull﹣timeemployee﹣stillworking40hoursaweek.NowIreneAstburyworksfrom9amto5pmdailyatthepetshopinMacclesfield2sheopenedwithherlatehusbandLes.Heryearsofhardworkhave3finalbeenacknowledgedafteracustomernominated提名hertobeCheshire'sWomanOfTheYear. PickingupherLifetimeAchievementawardproudIrene4declareshehadnoplans5retirefromher36﹣year﹣oldbusiness.IrenesaidIdon'tseeanyreasontogiveupwork.IlovecominghereandseeingmyfamilyandallthefriendsI6makeovertheyears.IworknotbecauseIhaveto7becauseIwantto. GranddaughterGayleParks31﹣whoworksalongsideherinthefamilybusiness﹣saiditremainedunknownastowhonominatedIrenefortheaward.ShesaidWedon'thaveanyideawhoputgrandmaforward.Whenwegotacall8sayshewasshort﹣listedwethoughtitwas9joke.Butthenwegotanofficialletterandwewereblownaway.Wearesoproudofher.It's10wonder.
设椭圆＝10＞b＞0的右顶点为A上顶点为B．已知椭圆的焦距为2直线AB的斜率为﹣．1求椭圆的标准方程2设直线ly＝kxk＜0与椭圆交于MN两点且点M在第二象限l与AB延长线交于点P若△BNP的面积是△BMN面积的3倍求k的值．
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