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若x，y满足，若z＝2x﹣3y有最小值为﹣7，则z的最大值是（ ）
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高三下学期数学《》真题及答案
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设z＝x＋y其中实数xy满足若z的最大值为6则z的最小值为
－3
－2
－1
0
已知xy满足约束条件1求目标函数z=2x+y的最大值和最小值;2求目标函数z=2x-y的最大值和最小
设正实数xyz满足x2－3xy＋4y2－z＝0则当取得最小值时x＋2y－z的最大值为________
已知xy满足约束条件试求解下列问题.1z＝的最大值和最小值2z＝的最大值和最小值3z＝|3x＋4y＋
已知实数xy满足条件若目标函数z=2x+y的最小值为3则其最大值为.
实数xy满足若z=ax+y的最大值为3a+9最小值为3a﹣3则a的取值范围是.
实数xyzw满足x≥y≥z≥w≥0且5x+4y+3z+6w=100.求x+y+z+w的最大值和最小值
若xy满足约束条件则z＝2x﹣3y的最小值为．
设D为xOy平面上的有界闭区域z=fxy在D上连续在D内可偏导且满足+若fxy在D内没有零点则fxy
(A) 最大值和最小值只能在边界上取到
(B) 最大值和最小值只能在区域内部取到
(C) 有最小值无最大值
(D) 有最大值无最小值
设xy满足则z＝x＋y
有最小值2，最大值3
有最小值2，无最大值
有最大值3，无最小值
既无最小值，也无最大值
设xy满足约束条件则z=2x﹣3y的最小值是
﹣7
﹣6
﹣5
﹣3
设D为xOy平面上的有界闭区域z=fxy在D上连续在D内可偏导且满足[*]+[*]若fxy在D内没有
最大值和最小值只能在边界上取到
最大值和最小值只能在区域内部取到
有最小值无最大值
有最大值无最小值
已知实数xy满足1若z＝x2＋y2求z的最大值和最小值2若z＝求z的最大值和最小值.
若xy满足若z＝2x﹣3y有最小值为﹣7则z的最大值是
7
14
18
20
若变量xy满足约束条件且z=5y﹣x的最大值为a最小值为b则a﹣b的值是.
若实数xyz满足x＋2y＋3z＝aa为常数求x2＋y2＋z2的最小值.
设z＝x＋y其中实数xy满足若z的最大值为6则z的最小值为
－3
－2
－1
0
若变量xy满足约束条件且z＝5y－x的最大值为a最小值为b则a－b的值是
48
30
24
16
若|x+1|+|x-2||y-2|+|y+1||z-3|+|z+1|=36则x+2y+3z的最大值是
若变量xy满足约束条件则z=2x+y的最大值和最小值分别为.
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Theideaofrobotrulersfriendsandlovershasbeenatopicofsciencefictionnovelsforyears. Butaccordingtoonemathematicalmodelofhowourbrainscreateconsciousnessemotionalmachineswillneverexist. Thisisbecausecomputerscan'thandleanyprocessthatcompletelyintegrates整合informationsotheycannotbeconsciousorfeeloneexpertsays. AmathematicalmodelforconsciousnessdevelopedbyGiulioTononiattheUniversityofWisconsin﹣Madisonsaysthattheabilitytointegrateinformationisakeyfeatureofconsciousness. Hebelievesthatintegratedinformationcan'tbebrokendownintosmallerpiecesinconsciousmindsbecausethebraincontextualizes将……融入背景information. Forexamplewhenweseearedcircleourbrainsdon'tseetheshapeasacolourlesscircleplusashapelesscolouredareaNewScientistreported.Insteadweseeitasawhole﹣aredcircleweunderstandthewiderpicture. It'seasyenoughformachinestoeditacollectionofindividualimages图象butmemoriesaremadeupofabankofintertwined相互交织的imagesandexperiencesandcannotbechangedinthesameway. Researchershaveusedmathematicstoshowthatcomputerscannothandlethecomplexprocessesneededtofitpiecesofinformationtogetherperfectly. Thereforeifconsciousnessisbasedontheintegrationoflotsofpiecesofinformationcomputerscan'tbeconsciousandcan'texperienceemotionslikehumans. ProfessorPhilMaguireoftheNationalUniversityofIrelandinMaynoothsaysthatconsciousnesscannotbecreatedinaphysicalmachineinlimitedtimeusinglimitedmemory. Itdoesn'tnecessarilymeanthatthereissomemagicgoingoninthebrainthatinvolvessomeforcesthatcan'tbeexplainedphysically.Itisjustsocomplexthatit'sbeyondourabilitiestochangeithesaid. Hisresearchmaymeanthatlonelyhumanswillnotfindlovewitharobottheyareunlikelytobemadetheirslaveseither. 1Whydoexpertsthinkemotionalmachineswon'texist? A.Machinescan'tsolveproblems. B.Machinescan'tintegrateinformation. C.Machinescan'thandleinformation. D.Machinescan'tcommunicatewithpeople. 2TheexamplementionedinParagraph6isusedtoshow. A.machinescannotfeel B.thebrainhasconsciousness C.machinescanrecognizeshapesandcolors D.thebraincancontextualizeinformation 3Itcanbelearnedfromthetextthat. A.theideaofrobotloverswon'tcometrue B.machinescaneditintertwinedimages C.robotscanfitpiecesofinformationtogetherperfectly D.computerscanexperienceemotionslikehumansoneday 4Whatwouldbethebesttitleforthetext? A.Howrobotswork B.Robotswillneverhavefeelings C.Willrobotsbecomepeople'sfriends? D.Whatwillrobotsbelikeinthefuture?
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同的增加删除或修改. 增加在缺词处加一个漏字符号Ʌ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. ThenewschoolyearisaroundcornersoIneedtobuysomethingtomychildrenandmyself.Thereforeyesterday'safternoonItookthemtoashoestoretobuyingsomenewshoes.Myyoungestkidswantedapairofsportsshoesandthusweboughtonepair.Myoldersonneededapairofcasualshoesforschool.andwewerefoundsomeonsale.Thefirstpairwhichhetriedonwasalittlesmall.soheputonotherpair.andtheyfittedhimperfectly.Mydaughterwantedbeautydressshoesandshegotsomehighheels.Imyselfboughtsomebootsbecausemyoldoneswerewearingout.
在“要致富先修路”的思想指导下近几年云南的交通有了快速的变化特别是“高铁网络”延伸到云南以后许多地区的经济和旅游发生了翻天覆地的变化高铁列车也成为人们外出旅行的重要交通工具．假期里小明和爸爸从昆明到某地去旅游从昆明到该地乘汽车行驶的路程约为800km高铁列车比汽车行驶的路程少50km高铁列车比汽车行驶的时间少5h．已知高铁列车的平均时速是汽车平均时速的2.5倍求高铁列车的平均时速．
HighlightsofIceland Day1 OurrepresentativewillmeetyouattheairportandabuswillbringyoutoyourhotelinthecapitalReykjavik.Aftercheckinginyourguidewillleadyoutovisitsomeofthecity'shighlights. Day2 WetourIceland^GoldenCircletakinginThingvellirNationalParkandgullfossWaterfallandseeTrokkurwhichspouts喷射a100﹣footjetofwaterintotheairevery3﹣5minutes. Day3 Day3isleftfreesothatyoucantryoutouroptionaltours.ExploretheThorsmorkValleyonajeepride.Anotheroptionistodriveoutontotheglaciers冰川andtakeasnowmobiletour.Whale﹣watchingboattripsarealsoavailablefromReykjavikharbour. Day4 Thetourendsatthecityairport. UsefulInformation •ThelocalcurrencyistheIcelandicKronaISK.Theoptionaltoursonday3costextraandaminimumof4peopleisrequiredforboththejeepandsnowmobilingtours. CurrentcostsThorsmorkJeeptour27000ISKsnowmobiletour34200ISKwhale﹣watchingsummeronly9000ISK. •Tippingisvoluntarybutisexpectedinthispartoftheworldforworkersinthetourismindustry. •Youmusthavetravelinsurancetotravelonourtours.Youcanarrangeforthisyourselforbuyitthroughourcompany. •Youcaneitherbookaflightwithusorarrangeyourownflight.Ifyouchoosethelatteryouwillhavetomakeyourownwaytothehoteldetailsofwhichwillbesenttoyouinadvance. 1OnwhichdaycanthetouristsseeGullfossWaterfall? A.Day1. B.Day2. C.Day3. D.Day4. 2Whatcanbelearnedaboutthewhale﹣watchingtour? A.Itisoneoftheoptionaltours. B.Itisavailableallyearround. C.Itcostsmorethanthesnowmobiletour. D.Itrequiresatleastfourpeopleforeachtour. 3Whatisrequiredofthetourists? A.Tippingtheirguides. B.Bookingaflightwiththetourcompany. C.Reachingtheirhotelinadvance. D.Buyingtravelinsurance.
假定你是校学生会__李华上周你校组织一个文化交流团到英国某高中进行文化交流现已回国.请你代表你校交流团给英国活动负责人David写一封信内容包括1.感谢对方的招待2.此行的体验和收获3.邀请对方暑假来中国体验中国文化.注意1.字数100左右开头结尾已为你写好不计入总词数2.可以适当增加细节以使行文连贯.DearDavidWehavebeenbackhomesafelyfromEngland.YoursLiHua
如图AB∥CDAD与BC相交于点OCD＝3ABS△ODC＝60则S△OAB＝．
大理古城简称榆城位居风光亮丽的苍山脚下是全国首批历史文化名城之一．它东临洱海西枕苍山城楼雄伟风光优美引来无数旅客前来观光．“十一”期间相关部门对到大理观光的游客的出行方式进行了随机抽样调查整理绘制了两幅统计图尚不完整根据图中信息下列结论错误的是
解不等式组．
Rt△ABC中∠C＝90°∠BAC＝30°BC＝84DE分别在射线BCAC上AD与BE交于F．1从顶点A所作三角形中线长为2若D恰为BC边中点E在边AC上且AEEC＝61求∠AFE3点M在AC边上AM＝56AD与BE所成锐角为60°当BF与MF的差的绝对值最小时求CE．
VolunteersarevitallyimportantforMelbourne'stourism.TheyprovideinformationonMelbourneforaroundtwomillionvisitorseachyear.TheirloveandknowledgeofthecityaddtoMelbourne'sreputationasafriendlywelcomingandculturallyvibrantcity.Ifyouwouldliketoreceiveanemailadvisingyouonthenextrecruitment招募sessionpleaseemailtourism@melbourne.vic.gov.au.TheCityofMelbourne'stourismbranchgenerallyconductstwovolunteerrecruitmentintakeseachyearforthefollowingtourismprograms*CityAmbassadors*MelbourneVisitorBoothatBourkeStreetMall*MelbourneVisitorCentreatFederationSquare*MelbourneGreeterServicePlacesarelimitedandpotentialvolunteersmustparticipateinaselectionprocessbasedonthefollowingcriteria.Volunteersmustbe*passionateaboutMelbourne*customerservicefocused*familiarwithcomputer*availableforonefour﹣hourshift轮班eithermorningorafternooneveryfortnightforaminimumofoneyear*teamplayerswholovemeetingpeople*abletodemonstrateacommitmenttotheCityofMelbourne'svaluesMoreinformationTofindoutmoreaboutbecomingavolunteercontactusonlineorphonetheCityofMelbourne'sVolunteerProjectOfficerTourismMelbourneon0396589658.ForothervolunteeringopportunitiesseenationalvolunteerrecruitmentwebsiteGoVolunteer.1WhichofthefollowingisNOToneofthequalificationstobeavolunteer?A.Beingwillingtocooperate.B.Havingcomputerskills.C.Beingabletodoshiftworkeverynightforayear.D.HavingpassionforMelbourne.2Howcanyougetothervolunteeringchances?A.Byemailingtourism@melbourne.vie.gov.au.B.Byseeingnationalvolunteerrecruitmentwebsite.C.ByphoningtheCityofMelbourne'sVolunteerProjectOfficer.D.BycontactingTourismMelbourneonline.3Whereisthetextmostprobablytakenfrom?A.Agovernmentwebsite.B.Aradioreport.C.Abookreview.D.Ageographytextbook.4Whatmaybethebesttitleforthetext?A.GuidetoTouringinMelbourneB.WelcometotheCityofMelbourne!C.DoesVolunteeringPayBack?D.TourismVolunteerProgram!
Pictureaniceberg冰山.You'llprobablyimaginesomethingwhiteassnowrisingupoutofabluesea.Buticebergscanbeallsortsofshades.Theycanbefromafrostybluetoanattractivegreen. Researchersandsailorshaveobservedemerald翠绿色icebergsforyears.Alargepieceoficemast﹣highandgreenasemeraldevenappearsinSamuelTaylorColeridge's1834poem.Buttheyhaven'tfoundoutexactlywhytheseicebergslookthewaytheydo. AnewpaperledbyStephenWarrenwaspublished.Itallhastodowithwhaticebergsaremadeoutof.Icebergsbreakoffglaciers冰川oriceshelveswhichhappensmainlyaroundAntarcticaandGreenland.Theybegintheirlivesassnowfallthataccumulatesovertime.So.icebergscontainairpocketswiththeformofbubblesthatspreadlight.Withsomeexceptionsandrarelinesglaciericetendstolookbluishwhite. AtfirstWarrenguessedthatthegreenwasaproductofmeltcarbon.Anditcamefromrottingplantsorseaanimals.Butsamples样本didn'tproveit.AnotherideastartedtotakeshapeaftertheyhadfoundahighconcentrationofironinasampleofseaicefromtheAmeryIceShelf. Whenglaciersrubacrosslandtheyproducewhat'sknownasglacierflour.Itisaproductofbedrockbeinggroundclownbythemovingmass.Asglaciersmoveawaytheseremainsareusuallywashedoutintowater.inparticlessometimestoosmalltobenoticeabletoyoureyes.Butonland.soilandrockscontainironoxidesthatoftenhaverosycolors.likeredsyellowsandbrowns﹣andsincetheseaicecontained500timesmoreironthantheglaciericeWarrenwonderedwhethertheremainswereresponsibleforicebergstakingonagreenappearance. Hedoesn'tknowforsure.He'shopingtosecuremoneysothathecanreturntotheareaandstudytheicebergsthemselves. 1WhyisSamuelTaylorColeridge'spoemmentionedinthetext? A.Ittellswhyicebergslookthewaytheydo. B.Itdescribesvividlywhaticebergsarelike. C.Itsayscausesoftheappearanceoficebergs. D.Itprovestheexistenceofcolorfulicebergs. 2WhatcanweknowaboutStephenWarren'spaper? A.Itdrawsonresearchers'andsailors'views. B.Itistherecordofthemovementoficebergs. C.Ittalksabouthowicebergscomeintobeing. D.Itisacollectionofvarioussocialphenomena. 3Whatdoestheunderlinedworditinparagraph4referto? A.Asampleofseaice. B.Warren'sfirstguess. C.Warren'sideaoniron. D.Aproductofmeltcarbon. 4Whatisparagraph5mainlyabout? A.Thepossiblereasonwhyicebergslookgreen. B.Wheremostoficebergseventuallydisappear. C.Howicebergstakeinthecolorsfromglaciers. D.Thewayinwhichicebergsbreaksoffglaciers.
2019年的元宵月不仅恰逢“年度最大最圆月”还是“十五月亮十五圆”最圆时刻出现在19日23时54分．月球过近地点的距离只有35.68万千米是月球全年距离地球最近的一刻此时月亮直径最大把数据35.68万千米用科学记数法表示为千米．
阅读材料求1+2+22+23+24+…+210的值． 解设S＝1+2+22+23+24+…+210① 将等式两边同时乘2得2S＝2+22+23+24+…+210+211② ②﹣①得2S﹣S＝211﹣1即S＝﹣1． 请你仿照此法计算 1求1+3+32+33+34+…+32019的值 2观察归纳上述过程并直接写出下列式子的结果a+aq+aq2+aq3+aq4+aq5+…aqn＝并证明．
如图在四边形ABCD中AB∥CD∠ABC＝∠ADCDE⊥AC垂足为E．DC＝7连接BE． 1求证四边形ABCD是平行四边形 2若△ADE的面积为∠DAC＝60°求四边形ABCD的周长．
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.错误涉及一个单词的增加删除或修改. 增加在缺词处加一个漏字符号∧并在其下面写出该加的词. 删除把多余的词用斜线\划掉. 修改在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改仅限一词. 2.只允许修改10处多者从第11处起不计分. MylittlebrotherandIwentshoppinginnewlyopenedsupermarketinourcitylastMonday.Wetastedalittledeliciouscheesebiscuitsandbuythreeboxesofcandies.SeenoneofmyfavouritechocolatecakesIquickenedmystepsthroughthecrowd.AfewminuteslateIcouldn'tfindmybrotherandgotanxious.Sincethereweresomanypeopleinthesupermarketsoitwasquitetoughformetofindher.Ihadtoaskasalesmanforsomeadvices.Itwasn'tlongafterthesalesmanfoundaloudspeakerandstartedtosearchformybrother.ThanksforthesalesmanImanagedtofindmybrotheratlast.
设…． 设则S＝用含n的代数式表示其中n为正整数．
HalloweenComingOut Amanwasshotinthefaceduringabankrobbery.Thatwasthenewsaboutmefiveyearsago.FromthenonIneverlookedina1itevenscaredmyselfwhenseeingmydestroyedface.Ilivedinmyhousealonewithoutoutsidecontact.ButonenightIwasmakingan2.ItwasHalloween. Whatafittingnightformeto3!Ilongedforhumancontact.WhenmypumpkinlanternsmiledatoothywelcomeinmyfrontdoorIheardfootstepsandgiggling咯咯的笑aschildrencameclosetomyhouse. Trickortreattheycried. Myhandsstartedto4.Iopenedthedoorandgavethema5smilethroughmydamagedlipsbeneatharoughscarwheremynoseonce6. Doyouwantatrickordoyouwantatreat?Myvoicesoundedmorelikeaghost.The7expressiononthechildren'sfacessuggestedeverything. Treat!They8pickedacandyortwofrommybucketandrantothe9oftheirparents. Iclosedthedoorandpressedmybackagainstit.IfeltdizzybutI10it.Thenthebellrang.Trickortreat.a11voicecametome.IopenedthedoortofindasmallgirlwearingaShirleyTemplemask. HiShirley.Ispokequietlynotto12her.Aren'tyoubeautifultonight? ShestaredatherfeetandshookherheadNo. Yesyouare.You'reShirleyTemplethemostbeautifulgirlintheworld. Shelookedupatmeandpulledher13totheside.Seeingherdeformed变形的facemyheartmissedabeat. WellIthinkyouarebeautifuldarling.Isaidgently. Atthewordshereyesconnectedwithmine.Anuncertainhandreachedtowardmybucketandtookonepieceofcandy.Thankyou.Hervoicewasa14.Sheturnedandrantohermother.Inoddedmyheadtohermotherandgavethembotha15. Iclosedmydoorandturnedoffmygatelamp.My16lifebeganagain. ThenextmorningIheardmydoorbellring.Itriedtoignoreit17itrangagain.IwenttothedoorandcalledoutWho'sthere? It'sShirleyTempleandherMom. Iopenedthedoorinafew18andlooked.Itwasthewomanandherdaughterwithouthermask.BeforeIspokethemothersaidMygirlsaidshewantedtomeetyou.Iwatchedtearsstartto19inthemother'seyes.Thisisherfirsttimeoutsidewithouthermask. Ipulledthedooropenandthatwasalsothefirsttimeinfiveyearsformetoinvitesomeoneintomy20. 1A.mirror B.wallet C.pocket D.bank 2A.expectation B.appointment C.introduction D.exception 3A.act B.stay C.appear D.flee 4A.shake B.cross C.dance D.tap 5A.bitter B.friendly C.simple D.quiet 6A.lived B.sat C.breathed D.slept 7A.moved B.excited C.shocked D.puzzled 8A.easily B.politely C.sadly D.quickly 9A.security B.shadow C.defense D.sight 10A.finished B.promoted C.got D.did 11A.thin B.loud C.claim D.clear 12A.interrupt B.scare C.discourage D.cheat 13A.gloves B.hat C.mask D.glasses 14A.whistle B.whisper C.signal D.sigh 15A.glance B.wave C.hand D.surprise 16A.busy B.social C.meaningful D.lonely 17A.for B.so C.but D.or 18A.seconds B.efforts C.inches D.steps 19A.well B.dry C.freeze D.fix 20A.future B.story C.mind D.life.
DutchdesignerDaanRoosegaardehasspentmuchofhistimeseekingartisticsolutions解决方案tosolveourenvironmentalproblems.HispastprojectsincludeBioluminescent生物发光TreestolightstreetsaSmog﹣FreeTowertocleanBeijing'spollutedair.andGatesofLight.whichusestheheadlampsofpassingcarstolightupthe60floodgatesoftheAfsluitdijkamajordamintheNetherlands.Nowheishopingtousehisskillstosolveapressingglobalproblem﹣spacejunk! Scientistsguessthatthereareover500000bitsoflargerubbish.TodealwiththeproblemRoosegaardeintendstoachievehisgoalbyeducatingthepublicabouttheneedofthesituationandcomingupwithpossiblesolutions.Theplan.calledtheSpaceWasteLab.startedinOctober2018withalaser激光showintheNetherlands.TheuniqueoutdoorartworkofLEDsusedreal﹣timetrackinginformationtopointatpiecesofspacejunkfloatingataltitudesof200to20000kilometers.Theexperiencewasdesignedtomakethepublicknowmoreabouthowmuchspacejunkthereare. Tofindasolutionthedesignerhasbeenthinkingwithexperts.OneoftheprojectsbeingconsideredisShootingStarswhichattemptstoreintroducethetrashtotheatmosphereinacontrolledway.Uponreentry.thewastewouldburnintheatmospherelikeashootingstar.Roosegaardeenvisagesthatifsuccessful.burningspacetrashcouldsomedayreplacefireworksatlargepublicevents! InSeptember2018.theRemoveDEBRISsatellitesuccessfullysentanettocatchatargetwhileorbitingatanaltitudeofabout300kilometers190miles.Sometimethisyear.thecapsulewillsetfreeaharpoonthathasbeendesignedtoremovespacetrash.AttheendofitstaskRemoveDEBRISwillletgoasailtobringthesatelliteitself.and.hopefullysometrashbackintotheatmosphere.whereitwillburnup. 1WhatcanweinferaboutDaanRoosegaarde? A.Heistooaggressivetoputforwardgoodplans. B.Heiscreativeinsolvingenvironmentalproblems. C.Heisfondofspendingallofhistimeseekingartskills. D.Heissensitivetoartreflectedinenvironmentalprojects. 2WhywasalasershowheldinOctober2018? A.Toconfirmreal﹣timeinformationaboutspacetrash. B.ToshowthegreatbeautyofLEDtocommonpeople. C.Toraisepublicawarenessoftheamountofspacetrash. D.Toinspirepeopletoconsiderthesolutiontospacetrash. 3Whatdoestheunderlinedwordenvisageinparagraph3probablymean? A.Suspect. B.Demand. C.Advise. D.Imagine. 4Whatisthefunctionofasail? A.Bringingthesatellitetoatmospheretoburn. B.Keepingtrashtravelingalongitsownorbit. C.Takingthesatelliteawayfromatmosphere. D.Removingspacetrashoutofthecapsule.
AfewyearsagomywifeandItookatriptoCostaRica.Uponarrivalwe1acarandheadedouttoourfirstdestinationwhichwasafewhoursaway.Ihada2soIfiguredI'dbeingreatcondition.About20minutesintothedriveIfoundmyselfpractically3intheunmarkedstreetsanddirtyroads.Upset.IturnedtoSiriavirtual虚拟的assistantinmyphoneforhelp. Itypedthe4toourdestinationinmyphoneandinstantlySirihad5thebestroute路线togetthereandwewereonourway. Theonly6wasthatthingsdidn'talwaysgothewayIthoughttheywould.Withthestreetsnotbeingwell7Iwouldsometimesmissaturnandheadinthe8direction.LuckilySirinevergot9withme.AnytimeImissedaturnSiriwouldsimply10andsayRecalculatingroute.11route.AndwithinafewsecondsSiriwouldhaveanewroute12togetustoourdestination. SometimesthenewroutemeantIhadto13totherightturnandsometimesshefoundadifferentroutethattookmynewlocationinto14Eventuallywemadeittoourhotel15andenjoyedsomebeautifulsceneryalongtheway. Mostpeoplemakethe16ofthinkingthatsuccessandhappinesscomefromsomeonesettingagoalandthen17straighttowardsit.The18isthatthereisnostraightpathtosuccess.Thereisn'teventhe19path.Therearemanypathsthatcangetyoutoyourgoals.Youjusthavetobe20torecalculateyourroutewhenyoumissaturnorthereissomethinginyourway. 1A.produced B.repaired C.rented D.purchased 2A.car B.phone C.compass D.map 3A.absorbed B.lost C.experienced D.free 4A.address B.approach C.receipt D.schedule 5A.polished B.discovered C.opened D.managed 6A.fear B.difference C.sympathy D.problem 7A.marked B.paved C.arranged D.expanded 8A.illegal B.new C.wrong D.potential 9A.generous B.mad C.concerned D.cautious 10A.breakdown B.cutin C.getup D.goaway 11AAbandoning B.Cancelling C.Reaching D.Changing 12A.checked B.updated C.adjusted D.planned 13A.point B.lead C.return D.apply 14A.order B.direction C.account D.place 15A.safely B.frequently C.hungrily D.gradually 16A.mistake B.excuse C.accident D.trouble 17A.accumulating B.withdrawing C.marching D.fleeing 18A.answer B.truth C.condition D.privilege 19A.first B.suitable C.accurate D.only 20A.willing B.proud C.anxious D.ambitious
某校计划修建一个既是轴对称图形又是中心对称图形的花坛从学生中征集到设计方案有等腰三角形正五边形正六边形平行四边形菱形矩形圆等图案你认为符合条件的有几种
ThePalaceMuseumiscelebratingitsupcoming600thanniversary.Itsnewattempt1fillyoungergenerationswithcultureisafabulousmixofcelebritiesancienthistoryandmoderntechnology.ThePalaceMuseumishometo2rough1.86millionprecioushistoricalrelics遗迹andamong3theNorthSongDynastymasterpieceAlongtheRiverduringtheQingmingFestivalpaintedbyZhangZeduan4considertobeofgreatvalue.ThepaintinghassuchareputationofbeingChina'sMonaLisa5millionsofvisitorsareattractedtoenjoyit.The6originmasterpieceisstatic静态的anditseemsthatthegeneralpublicrarelyknows7thepaintingisattemptingtoconvey.Since2000thePalaceMuseum8cooperatewithtechnologycompaniestomakethesesilenthistoricalrelicscomealive.Thedigitalizedversionoftheworkcanbeshownonthegiantscreeninanexhibitionroom.Visitors9wearVRglasseswilltakeaboatandexploretheneighborhoodoftheBianRiver.Thankstomoderntechnologyalltheprecioushistoricalrelicswillbebrought10lifewiththeirobscure晦涩的wordseasiertounderstand.
如图是由5个相同的小正方体组成的立体图形这个立体图形的左视图是
如图反比例函数y＝图象与直线y＝﹣x交于AB两点将双曲线右半支沿射线AB方向平移与左半支交于CD．点A到达A′点A′B＝BOCE＝6则k＝．
计算|﹣2019|＝．
ItwasdaysorevenweekssinceIhadbeenleftontheisland.MyonlycompanionwasadogcalledPhillywhichhadsurvivedtheshipwreck.Memoriesofwhathappenedwerestillfresh. Themagnificenceoftheshiphadgivenusallafalsesenseofsecurity.Asthefirstsignsofthestormstartedourcaptainannouncedit'snothingmuchjustanotherstorm.Yethewaswrong!Thestormhittheshipsobadlythatlargeholesweremadeatthesidesoftheship.Asthefreezingwaterstartedrushinginourshipwasconsumedquicklybythedarkwater. MytrainofthoughtwasdisturbedbyPhillylickingmyhanddearly.Areyouhungry?Ispokemyfirstwordseversincetheshipwreckoccurred.Woofwoof!BarkedPhillyenthusiastically.Atthismomentmystomachgavealoudgrowltoo.Icouldnotrememberwhenmylastmealwasprobablyaten﹣coursedinnerontheship.AsIhadneverfishedbeforeIthoughtmaybeIcouldtrysomethingsimplerlikepickingfruits.WithPhillyatmysidearmedwithasharpbranchwewalkedintotheforestontheislandtogether.SuddenlyIthoughtIheardnoises.Couldtherebeanyoneelseonthisisland?Iwondered.Aswewerelookingforfruittreeswechancedupononethatboreyellowjuicy﹣lookingfruit.Phillystartedbarking﹣wehadcompany.Itwasadark﹣skinnedwomanholdingasharpspeardressedinfurandgrass.Ibackedawayfromherafraidthatshewouldbeaggressive.ThenIsawthatshewastryingtosaveus.Pointingherspearatthefruittreesheshookherheadstrongly. InoddedathertoshowIunderstoodwhatshewassaying.SignalingtoustofollowhersheturnedtowalkalongasmallpaththatIhadnevernoticed.Attheendofthesmallpaththerewasasmallvillage.Tearsofjoyfilledmyeyes. 1Whathappenedtotheshipthewriterhadbeenon? A.Itwasfrozeninthesea. B.Itwasturnedoverbythestorm. C.Itwasdesertedbecauseitwasinsecure. D.Itsankduetothedamagecausedbythestorm. 2AccordingtothepassagewhichofthefollowingcanbestdescribePhilly? A.Activeandfriendly. B.Caringbutaggressive. C.Smartandfaithful. D.Noisybutenthusiastic. 3Whydidthewriterwalkintotheforest? A.Totakeshelterfromthestorm. B.Togotoasmallvillage. C.Tofindsomeoneforhelp. D.Tolookforsomethingtoeat. 4Thewomanmostprobablytriedtotellthewriterthat. A.thefruittreewasn'tthebestchoice B.thefruitwasunfitforeating C.thewriterwasn'tallowedtopickthefruit D.shewasn'tafraidofthewriter
a﹣＝3则a2+＝．
如图AB是⊙O的直径且AB＝6．点C是⊙O上的一动点连接ACBC在AC的延长线上取一点D使得∠CBD＝∠DAB点G为DB的中点点E为BG的中点连接AE交BC于点F． 1试判断直线BD与⊙O的位置关系并说明理由 2当∠CGB＝60°时求的长 3当AE∥CG时连接GF若AF＝4求BD的长．
Screamifyouwanttochargeyourphone.ThankstothewondersofscienceridersonThorpePark'snewattractionarollercoaster过山车calledTheWalkingDeadcannowpowertheirsmartphonesbyscreamingloudly.That'sbecausetherearedevicesonitthat'harvestkineticenergy'动能.Theparkconductedresearchwhichshowsthatmillennials'biggestfearistheirphonesrunningoutofbatterysothedeviceshouldprovepopular.AlloftheWalkingDead'scarriageshavebeenfittedwiththeharvestingdeviceswhichnotonlyharvesttheenergyofscreamsbutthatfromg﹣forceandvibrations振动too.Theunitsarethenremovedfromthecarriagesbystaffanddepositedintoanon﹣sitemobilechargingpoint.ThorpeParksaid'Ifthrill﹣seekersarebraveenoughtoopentheireyestheywillseeasetofLEDlightsinbloodredpoweringupasguests'screamsbecomelouderthroughoutthespine﹣tingling90﹣secondexperience.'DesignedandinstalledbyresearchersatQueenMaryUniversityLondonandtheengineeringteamatThorpeParkResortthetechnologytookthreemonthstoimplement执行fromdesigntoinstallation.Itwillbeavailableatthethemeparkforaninitialtrialperiod.Ifthisprovessuccessfulthetechnologymaybecomeapermanentfixturefortheremainderofthe2018season.ThorpeParkResort'sJohnBurtonwhocameupwiththerideconceptsaid'TheWalkingDeadTheRideis15outof10onthescarefactorscale等级soitmakessensetobeabletocombineandusethepowerofourvisitors'screamsandtheride'svibrationstohelpsolveaproblemeachandeveryoneofusfaces﹣losingthechargeonourmobileswhenwe'reonadayout.'DrJoeBriscoeSchoolofEngineeringandMaterialsScienceatQueenMaryUniversityofLondonsaid'Thisisanexcitingconceptthatwillundoubtedlybeusedmorefrequentlyinthefuture.Thesystemusesaminienergyharvestertocapturethekineticenergytransferringittoaseparateelectricalcircuitandstorageunitwhichisenoughtochargeamobilephone.'1Wecanlearnfromthetextthat.A.aphoneshouldbeputintherollercoastertobechargedB.itwasJohnBurtonwhodesignedandinstalledthedeviceC.theenergyofscreamsg﹣forceandvibrationscanbeharvestedbythedeviceD.thetrialperiodofthetechnologywilllastthreemonths2Whatdoestheunderlinedword'spine﹣tingling'meaninParagraph4?A.Unforgettableandsatisfying.B.Interestingandinspiring.C.Exhaustingbutdelightful.D.Frighteningbutexciting.3WhatisDrJoeBriscoe'sattitudetowardthefutureofthenewconcept?A.Skeptical.B.Optimistic.C.Critical.D.Neutral.4What'sthemainideaofthetext?A.Thetraditionalwayofchargingyourphoneisonthewayout.B.Anewbatteryforpoweringyourphoneisinvented.C.Visitors'screaminThorpeParkcanbeusedtochargethephone.D.ThemosteffectivewayofchargingyourphonehasbeenfoundinThorpePark.
WhyYouShouldn'tPunishYourKidsForLyingIt'snoeasytasktostopyourchildrenlying.TherearemanyinfluencesTVmoviesvideogamesandsomegreatbooksinwhichliesarecommon.Childrenseeparentslietoothersonlytobepolite.MostparentsaddtothatwithtalesaboutthelivesandactivitiesofSantaClausortheToothFairytobringjoyortolessenfears.1butforsomechildrenlyingcanbecomeaproblem.Themostcommonreactionstochildrenwholieareexplainingwhyitiswrongandpunishingthem.2.Herearethreebettertoolssupportedbyresearchtouseinstead.PRAISEYoucouldaskyourchildtosaysomethingthathappenedatschoolthatistrue.Whenyourchildobeyspraisehimenthusiastically.Bespecific'Thatwasgreat!YoutoldmewhathappenedjustasIasked.Wow!'andgiveyourchildahugorahighfive.Aimforoneortwointeractions互动likethisaday.Ifyouhappento'catch'yourchildinaliesaysomethinglike'Thatisnottrueandcouldgetyouintroubleoutsideofthehome.'MODEL3.Thiscouldbeaboutsomethingthathappenedwhenyouwereachildorsomethingthathappenedduringtheday.Itneednotbedramatic.Anotheroptionistoplayagameatdinner.Eachpersontellsonethingthatwastruethatday.Againgivealittlepraisetothechildwhonormallyliesifheplaysalong.DECREASEPUNISHMENTANDMORALIZINGSomechildrenareunlikelytochangebehaviorordeveloptheconductyouwant.Thatdoesnotmeanyoucanignoretheirlyingorletitgo.Ratheruseverymildpunishmentlightscoldingshortlossofprivilegeabrieftime﹣out.4.Trytheseproceduresfortwotothreeweeksandseewhereyouare.Usuallyliescanbedroppedbythen.5butwiththerightencouragementcanbedramaticallylessened.A.ParentspunishchildrenbecausetheyareinapositionofgreaterpowerB.ButaswaysofchangingbehaviortheseareineffectiveC.TheythinkitunnecessaryforchildrentotellalieD.ParentsdothisoutofloveE.SeverepunishmentsarenotalwayseffectiveinactuallychangingthefrequencyoflyingF.YoushouldsetagoodexampletoyourkidsandexplicitlytellthetruthG.Itisunlikelythatlyingwillbecompletelyremoved
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