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已知直线l1：2x+y﹣5＝0，l2：x﹣2y＝0 （1）求直线l1和直线l2交点P的坐标； （2）若直线l经过点P且在两坐标轴上的截距互为相反数，求直线l的一般式方程．
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高二上学期数学《》真题及答案
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为了考察两个变量x和y之间的线性相关性甲乙两个同学各自独立地作10次和15次试验并且利用线性回归方法
直线l1和l2有交点(s，t)
直线l1和l2相交，但是交点未必是点(s，t)
直线l1和l2由于斜率相等，所以必定平行
直线l1和l2必定重合
已知两直线l12x－y－2＝0与l2x＋y＋3＝01直线l经过l1与l2的交点且与l2垂直求直线l的
已知4x﹣2y﹣12+=0求4x2y﹣4x2y2﹣2xy2的值.
一个圆切直线l1x－6y－10＝0于点P4－1且圆心在直线l25x－3y＝0上求该圆的方程.
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直线l1和l2必定重合
必有l1//l2
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已知直线l经过两直线l12x﹣y+4=0与l2x﹣y+5=0的交点且与直线x﹣2y﹣6=0垂直.1求
平面坐标系内有直线L1y=ax和直线L2y=bxa＞b＞0动点10沿逆时针方向绕原点做如下运动先沿垂
收敛于原点
发敞到无穷
沿矩形边界稳定地转圈
随机运动
已知直线l经过两条直线2x+3y﹣14=0和x+2y﹣8=0的交点且与直线2x﹣2y﹣5=0平行.Ⅰ
下列结论①若命题p∃x∈R.tanx＝1命题q∀x∈R.x2－x＋1>0.则命题p∧綈q是假命题②已
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已知抛物线y2=2pxp＞0过定点p0作两条互相垂直的直线l1l2l1与抛物线交于PQ两点l2与抛物
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（0，1）
（0，2）
（0，+∞）
（1，+∞）
设直线L14x+y-4＝0L22x-8y+15＝0为曲线Cy＝上的一点则
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（0，1）
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平面坐标系内有直线L1y=ax和直线L2y=-bxa>b>0动点10沿逆时针方向绕原点做如下运动先沿
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Weneedtoberesponsibleforourenvironment.Beingafrugalconsumer节俭的消费者isonewaytohelp.1 UseItUp. Youcanusethingsupinsteadofwastingthem.Squeeze挤thatlastbitoftoothpasteoutofthetube.2Don'tthrowawayanybitsofthebiscuitatthebottomofthebox. WearItOut. Youdonotalwaysneedtohavenewthings.Supposeyoursneakers运动鞋havebrokenlaces鞋带buttheystillfityou.Repairthemandwearthemlonger.Youdon'thavetohavethelatestiPhoneuntiltheoldonedoesn'tworkanymore.Thenyoucangetanewone.3 MakeItDo. Whensomethingyouwantisnotonhandlookforsomethingelsethatyoualreadyhavetotakeitsplace.Supposeyouarepackingyourlunchfortomorrowandwantabuttersandwich.Youareoutofbutter.Haveacheesesandwichinsteadsoyoucanuseallofthecheese.Learntofixbrokentoysinsteadofjustthrowingthemaway.4 5Thinkaboutallthosethingsthatyouwouldliketohave.Doyoureallyneedthem?HowlongwillyoureallyplaywiththatnewtoyyousawonTV?Makingthethingsthatwewantusesupourworld'sresources资源.Andgettingridofthethingswedon'twantanymoretakesupevenmoreresourcesandspace. A.Dowithoutit. B.Throwitaway. C.Whatexactlydoesthatmean? D.Doyouknowwhattoconsume? E.Usethelastlittlepieceofsoap. F.Withalittlethoughtyoucanmakesomethingdo. G.Thinktwicebeforereplacingsomethingthatstillworks.
ConfidenceComesFromTreatingOthersAsEquals There'sbeenrecentdiscussionoverChineseattitudestowardforeignerscausedbyanotherquarrelbetweenaforeignerandataxidriver.AccordingtothestudiesdescribedintheOxfordHandbookofChinesePsychologyChinesehavelowerself﹣confidencecomparedtoWesterners.YetdoestheresultstillapplytotheChinesepeopletoday? Yesandno.ForthemomentdifferentattitudestowardforeignerscanstillbefoundinChina'ssocietywithsomedisplayinglowself﹣confidencelikeForeignersareawesome令人敬畏的andWesterncountriesareawesome.Weshouldrespectthemandbeaspoliteaspossibleandshouldn'tletthemlookdownonusandafewunfriendlyopinionssuchasSomeforeignersarerudeanddisrespectfulandtheirlevelofcivility礼貌isfarbehindChina. Chineseusedtobelackinginself﹣confidence.ItmightstartfromthemodernhistoryafterthefailureintheOpiumwarsandthefollowinghumiliation耻辱ofbeingbullied被欺负andbroughttotheirkneesbyWesternguns.Andthedarkhistoryisstilltosomeextentaffectingourmentality心态today. ForsometimetheWesternworldrepresentsthebestofeverythinginsomeChineseeyes.Butourstateofmindisgraduallychanging.WhenaskedWhatmakesyoufeelproudofyourcountry?inschoolclassesinChinaanswersvaryfromtheWorldExpototheOlympicGamesfromathletestoastronautsfromthemushroomingskyscraperstobusymetropoliseswhichhaveallfilleduswithgrowingself﹣confidence. WhileansweringthequestionSinceChinaissogoodtodayandChinesepeoplearemoreconfidentwhyareanincreasingnumberofChineseemigratingabroad?ZhangWeiweiaprofessoratFudanUniversityrepliedthatatleast70percentofChinesemigrants移民becomemorepatriotic爱国的afterleavingtheirhomecountrynomatterwhethertheyhavebecomeanaturalizedcitizenofanothernationornot.Suchresultandexperiencesaremuchmoreconvincingandhavebettereffectthandozensofpatrioticeducationclasses. Thereisnoreasonforusnottobeself﹣confident.Weliveintheworld'ssecond﹣largesteconomy.Chinesenetfinancialassetspercapita人均纯金融资产andthepurchasingpowerofpeoplehaveseenasharprisewithmoreandmorepeoplestartingtopurchaseworksofartinsteadofonlynecessities.Theseallindicatearisingstandardoflifeandself﹣confidence. NeverthelessthepointofthechangingattitudestowardourselvesorothercountriesisnotrealizingothernationsarebetterorworsethanChinabuttreatingthemlikehowwetreatourfellowChinese.Thatiswhatconfidencemeansnotbeingcondescending屈尊notworshipingbutlookingeachotherintheeyewithtrustandrespect. 1AccordingtothetextwhataretheChineseattitudestowardforeignerstoday? A.Theyhavevariousattitudestowardforeigners. B.Theythinktheforeignersarealwaysrude. C.Theyalwaysspeakhighlyoftheforeigners. D.Theybelieveforeignersarejustcommonpeople. 2Chineseusedtolackself﹣confidencebecause. A.Theythoughttheforeignersweremysterious. B.Theyusedtothinkthemselveslesspowerful. C.Theyweredeeplyinfluencedbythedarkhistory. D.Theyoncebelievedforeignerswereawesome. 3AccordingtoZhangWeiweimostChinesemigrants. A.desiretobeacitizenofanothernation B.developastrongerlovefortheirhomecountry C.areunwillingtoreturntotheirmotherland D.serveasbadexamplesinpatrioticeducation 4What'sthemainideaofthepassage? A.Chineseshouldbeproudofthegreatachievementoftheircountry. B.Chinesehaveenoughconfidencetomakegreaterprogress. C.Chinesehavealowerself﹣confidencefacedwithforeigners. D.Chineseshouldbeconfidentandtaketheforeignersasequals.
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RunningforaDream IwillneverforgetthatNovemberday.Itwashotterthannormal.Thiswasthe1myfatherandIhadwaitedsolongforbecausewehadbeenworkingtowardsthisraceforthreeyears.Dozensoffamiliarfacesfromchurchandschoolflashedacrossmyview.Theyhadcome2me.Isawworryand3onmyfather'sface.Thentheracebegan! ForthefirsttwoandahalfmilesIfelt4.Ihadneverbeforebeensoreadyforsomething.Theweeksleadinguptotheracewerefilledwithcontrolled5andastrictdiet.Myfriendshadn'tseenmeinweeksbuttheyunderstoodthe6requiredtomakemydreamareality.AsinallofmyracesIdidn't7outinthefrontIlovedthepleasureofpassingpeopleasmystrengthovertooktheirprematurespeed. Thenwithoutwarningmystrengthbegantodecrease.NeckandneckwithoneofmygreatestcompetitorsI8seethefinishline.Ihadbegunthefinaldashinto9whenmykneesbecameweakandmylegsgaveway.NothingIcoulddowouldmakethem10weight. Iwatchedasrunnersrushedbyme.11IknewmydreamsofvictoryweredestroyedIhadtofinishtherace.Howevermylegshurtbadly.Withallofthe12leftinmeIgotonmyhandsandkneesandcrawled爬inchbyinchacrossthefinishline.Voicesboth13andfamiliarcheeredmeon.Theygavemethecouragetokeep14untiltheveryend. Thedoctorswerethereinsecondsbutmyeyessearchedthecrowdforhim.TherewasonlyonepersonIwantedto15to.IwhisperedI'msosorryDadI'msosorryI16you.HelookedatmesayingYoucouldneverdisappointme.Sometimesthesethingsjust17.Allthatmattersisthatyoudidyourbest. Butweworkedso18.Whataboutourdream?HereachedoverformyhandandsaidDon'tyouknowthatyouaremydreamandithascometrue? Itwasn'tlongbeforemyrunningshoeswerebackonmarkinga19pathformyjourneyIlearnedthatallofthemilesthetearsthesweatandthepainmydadandIexperiencedtogetherwerenotfora20.WhatIrealizedthoughwasthattohimIwasthegreatestprizehehadeverwon. 1A.dream B.weather C.result D.day 2A.for B.to C.across D.over 3A.coldness B.astonishment C.excitement D.amusement 4A.proud B.great C.nervous D.afraid 5A.programs B.studies C.instructions D.practices 6A.understood B.blamed C.criticized D.concerned 7A.look B.move C.start D.come 8A.should B.could C.must D.need 9A.relief B.spirit C.pleasure D.glory 10A.give B.feel C.hold D.add 11A.Where B.Because C.If D.Although 12A.trust B.emotion C.strength D.confidence 13A.loud B.foreign C.rough D.firm 14A.going B.running C.fighting D.training 15A.refer B.talk C.listen D.agree 16A.frightened B.disturbed C.disappointed D.bored 17A.develop B.change C.follow D.happen 18A.late B.hard C.closely D.quickly 19A.new B.near C.rough D.narrow 20A.wish B.duty C.rank D.race
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设n为正整数集合A＝{T|T＝t1t2…tntk∈{01}k＝12…n}．对于集合A中的任意元素X＝x1x2…xn和Y＝y1y2…yn记dXY＝． Ⅰ当n＝3时若X＝110Y＝011求dXX和dXY的值 Ⅱ当n＝4时设B是A的子集且满足对于B中的任意元素XY当XY相同时dXY是偶数当XY不同时dXY是奇数．求集合B中元素个数的最大值 Ⅲ给定不小于2的n设B是A的子集且满足对于B中的任意两个不同的元素XYdXY＝n．写出一个集合B使其元素个数最多并说明理由．
某几何体的三视图如图所示该几何体的体积是
Riseandshineallday Makingtheseeasytaskspartofyourmorningschedulewillimproveyournutritionenergyandmoodtoday﹣andbeyond. Stretchinbed Trythisevenbeforeyouopenyoureyes.Liftonearmandbeginbystretchingeachfingerthenyourhandthenyourwristandthenyourwholearm.1.Thenstretchyourtoesfeetanklesandlegs.Finallyendwithaneckandbackstretchthatpushesyououtofbed.Thispowerposemakesyoufeelmoreconfidentalldaylong. 2Workingoutbeforeyoueatencouragesyourbodytoburnmorefatforenergyratherthanrelyingoncarbohydrates碳水化合物fromfood.Inastudyparticipantswhoexercisedafterbreakfaststillgainedweightbutthosewhoexercisedonanemptystomachdidnot. Turnonthemusic 3.Ifanyoneplaysaninstrumentandifyouhavealittletimemorningistheperfecttimetopracticeasitpreparesyourbrainforlearning.Onestudyfoundthatbothplayingandlisteningtomusichelpimproveacademicperformancein16differentwaysincludingincreasingfocusandmemory. Enjoysomefun Manypeoplefeartofaceanewdayofworkschoolorchores.4.Thiscanbehavingacupofcoffeeasyoureadyourfavoriteblogetc.Chooseactivitiesyouenjoyandthatsetyouonagoodpathfortheday You'veimprovedyourstateofmindyourhealthandyourproductivity﹣allbeforetheweekdayhasevenbegun. 5. A.Picksomethingenergeticthatyouandothersinthehouseenjoyandputitonwhileyougetready B.Nowyou'rereadytoconqueryourto﹣dolistfortodayandeveryday C.Doregularexerciseinthemorning D.Moveontotheotherarm E.Exerciseabit﹣Onanemptystomach F.Takeuptheentirelengthofthebedwhenyoustretch G.Butifthefirstthingyoudoispleasantyou'llfinditmucheasiertogetgoing
IntheWestsomepeoplebelievethatpersonalitycanbepredictedaccordingtothebloodtype1thepersonwasbornwith.PeoplewithbloodtypeAforexample2considermorelikelytobeserioushard﹣workingandquietwhilepeoplewithbloodtypeOarelikelytobepopularandoutgoingyetoftenunable3finishwhattheystart.Thoughthisbeliefcontinuestobestrongsomepeoplequestionwhetheritistrue. Theblood﹣typepersonalitytheory4startinJapanin1927whenFurukawaTakehinoticedpersonalitysimilaritiesand5differentamonghisworkers.Thisideasoonwentoutoffashion6itwasbroughtbackbyaJapanesetelevisionhostnamedToshitakaNomiinthe1970s.ThebeliefisstillstronginJapanandisincreasinglypopularinneighboringcountries.MostAsiansmightbelieve7theblood﹣typetheorybutformanyitseems8harmandnotsomethingtobetakentooseriously. Isthebelieftrue?ThescientistsinAsialargelydismiss摒弃thebeliefasamodern﹣daysuperstition迷信.Moststudieshavefailedtofindanystrong9connectbetweenbloodandpersonality.10generalscientistswarnagainstmakingpredictionsorimportantdecisionsbasedonthisquestionabletheory.
如图所示正方形ABCD的边长为2椭圆C1＝1a＞b＞0及双曲线C2＝1m＞0n＞0均以正方形顶点BD为焦点且经过线段AB的中点E则椭圆C1与双曲线C2离心率之比为．
AllAboardforaFamilyTripbyTrain Ifyou'relookingforafamilyvacationidealooknofurther.ExploreAmericawithAmtrak.Onthetrainyourfamilywillhaveplentyofroomtospreadoutandrelax. OnceonboardthefamilycantakeinthesceneryfromtheSightseerLounge观景车厢.PlusmostofourovernighttrainsfeatureDiningcarsthatservethreemealsadaywithfullmenusandtableservice.Ifyou'relookingforlighterfaregrababitetoeatoradrinkintheCafécar.YoucanalsoreserveSleepingcaraccommodationsandletthegentlerhythmsofthetrainswayyoutosleep.It'sthebestwaytoarriveatyourdestinationrestedandreadytogo. LearnMoreAbouttheOnboardExperienceonwww.amtrak.com •ADiningExperiencelikeNoOther Fromfullsit﹣downmealstomoreinformalfoodservicemanytrainshaveoneormoreoptionforonboarddining.Ifyou'renothungryyoumightstarttohearyourstomachrumbling腹鸣afterlookingatourmenus.Weprovideyouwithmorediningchoicesonboarddiningreservationsandthedifferenttypesofdiningcarslikelongdistancedinningcarloungecarandcafécar. •SleepingAccommodations Sleepingaccommodationsareavailableonmostlong﹣distanceroutes.Amtraktrainstravelingonlong﹣distanceroutestypicallyuseeithertwo﹣levelSuperlinerorone﹣levelViewlinertraincarequipmenteachofwhichincludebedroomsarrangedinvariousconfigurationsandprivateandpublicbathroomsandshowers. •SeatingAccommodations OnmostAmtraktrainsyouhavethreeoptionsforseatingaccommodations.Theavailabilityoftheseoptionsvariesdependingonyourrouteandthetypeoftrainequipmentinuse CoachClassDesignedforYoutoRelax. BusinessClassMoreAmenities.MoreComfort. FirstClassExclusivelyonAcelaExpress. 1Thefamilycansavealittlemoneybyeatingat. A.dinningcar B.viewliner C.cafécar D.superliner 2HowmanychoicesdoesAmtraktraincanofferinseatingaccommodations? A.Two. B.Three. C.Four. D.Five. 3Fromthepassagewecanknowthat. A.alltrainsprovidesleepingaccommodations B.noovernighttrainsfeatureDiningcarsatall C.tripbytrainistheonlywaytotravelrested D.manytrainshavemanyanoptionfordining
ZooanimalsVSanimalsinthewild Zooanimalsusuallylivelongerthantheirwildcounterparts.Thisisbecausetheyhaveaccesstomedicalcareandbetternutritioninzoos.Moreoverthereisalackofpredators捕食者.1Elderlywildanimalslosetheirstrengthabilitytofindanddigestfoodandoftenlosetheirsocialstandingintheirspeciessocialstructure.Zoosarelearninghowtocareforoldanimals. Boredomisabigproblemforanimalsinzoosandsomethinganimalsinthewilddonothavetoface.Animalexpertsbelievethatasmallplaceproducesboredom.2Theyalsoprovidecompanionsandhidepiecesoffoodsotheanimalshavetosearchforitasinthewild. 3AcaseinpointistheAsiaticwildhorse.Thespecieswashuntedtoextinctioninthewildby1969.Theentireworldpopulationnowlivesinzoosandnaturepreserves.ThelargestpopulationiskeptattheNationalZooinWashington.D.C.Allofthoseanimalswerezoo﹣born. Animalslivinginthewildmaycomeintocontactwithpeople.Theanimalsmayhuntlivestock家畜oreatfarmers'crops.4Ingoodzoospeoplecanseethattheseanimalsarenotjustabletomaketroublebutleadcomplexlives.Thiscanhelppeoplesavetheanimalandthehabitatneededtokeeptheanimalaliveinthewild. Animalsoftenreproducebetterwhentheyareinthewild.5Oneoftheremarkableexamplesisthefemalegiantpanda.Usingartificial人工的meanshashelpedraisetheworldwidepandapopulation.Alsobytryingtorecreatetheanimal'snaturallivingconditionsasmuchaspossiblezooanimalswillbreed. A.Thegoalsofzooshavechanged. B.Howeversomeanimalsareanexception C.Iftheyliveinthewildtheyhavetobattleagainstthem. D.Asaresulttheyareconsideredharmfulandarehunted. E.Evensoitoftenleavesonetowonderiftheanimalslivewell. F.Forsomespecieslivinginzoosistheonlywaythespeciescansurvive. G.Sogoodzooshavereplacedallmetalcagesforthoseanimalsthatusedtoliveinlargeareas.
假设你是李华.你的外国笔友打算于7月来中国特来信了解中国人的社交习俗.请你用英语回一封信从以下几个方面作具体介绍 1.见面时的问候方式 2.接收礼物时的回应方式 3.餐宴礼节. 注意1.词数100左右信的开头和结束语已写好不计入总词数 2.可根据内容要点适当增加细节使行文连贯. DearJane Gladtohearfromyouandyou'rewelcometoChinainJuly. Yourssincerely LiHua
在极坐标系中若点A在圆Cρ＝1上则点A到直线lρcosθ+sinθ＝2距离的最大值为．
Withthepassingof2018andSpringFestivalwe1startanewimportantyearalready. Thisyearisoneofthefinalsteppingstonestobecominga2moderateprosperoussocietyin2020.Meanwhile2019marksthe70thanniversaryofthefoundingofthePeople'sRepublicofChina.Topreparefor2019thegovernmentmade3iteconomicagenda事项clearattheCentralEconomicWorkConference4attendbythecountry'sleadersinBeijinginDecember. Greatattentionwillkeepon5paytoChina'sgrowthperformancein2019.Tomeetthetargetofdoubling2010GDPbytheendof2020itneedstoaverageabout6.3percentthisyearandnext. MeanwhileChinawillhostthesecondBeltandRoadForumforInternationalCooperationinApril.AtthiseventtheBeltandRoadInitiative6hashugepotentialtodriveeconomicgrowthwilltakegreatershape. Thisyearisalsolikelytopavethewayforanumberoftechnological7advance.Chinaisexpectedtorollout5Gthenextgenerationof8wiretechnologynextyear.It'supto100timesfaster9thecurrent4Gtechnology. ItwillbeayearforChinatoreflect10itspastandfuturedirection
设函数则下列结论中正确的是
如图在四棱柱ABCD﹣A1B1C1D1中侧棱A1A⊥底面ABCDAB⊥ACAB＝1AC＝AA1＝2AD＝CD＝点E为线段AA1上的点且AE＝． Ⅰ求证BE⊥平面ACB1 Ⅱ求二面角D1﹣AC﹣B1的余弦值 Ⅲ判断棱A1B1上是否存在点F使得直线DF∥平面ACB1若存在求线段A1F的长若不存在说明理由．
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. I'mdelightedtoknowyoushowedagreatinterestinChinesetablemanners.NowIwouldliketoshareyouhowtobehaveproperlywhenweareinvitedtodinner. Tobeginwiththehostwillreserveaspecialseatfortheguestwhichishighlyhonoredonsuchanoccasionbutisexpectedtobethefirsttotastethefoodserved.BesidechopsticksandspoonsareusuallyusedwhenyouareeatinginChina.Thirdyouarenotsupposedtomakinganoisewhileeatingsoup.Lastbutnotleastremembertothankthehostforthedeliciousfoodhehasbeenofferedwhichwillsurelymakehimhappily. Ihopemyadviceswillbeofhelptoyou.
NotallofGeorgeH.W.Bush'sextendedfamilymemberswereinvitedtohisWashingtonD.C.memorialservice. NearlyaweekaftermanypaidtheirrespectsattheWashingtonNationalCathedralSharonBushwhowasmarriedtothe41stpresident'ssonNeilfrom1980to2003toldPageSixthatshewasallegedlyunabletoattendthefuneralaftershewastoldbyherex﹣husband'ssecretarythattherewerenotenoughseats. Iwasgoingtotakethetraindown.Iwantedtopaymyrespects.ButIpaidmyrespectsbyraisingthreewonderfulchildrenduringa23﹣yearmarriageSharontoldtheOutlet. NeilandSharonsharethreechildrensonPierceanddaughtersAshleyandLaurenBushLaurenwhogaveareadingatthefuneralwherethefatherofthreeattendedwithhissecondwifeMariaAndrewswhomhewedin2004. WhiletheD.C.memorialservicewastakingplaceSharonrecalledhavinglunchwithLadyGaga'smotherCynthiaGermanottaandpublishingheiressAnneHearst. ThoughshewassnubbedfromthefuneralSharonsharedphotosonInstagramtohonorherformerfather﹣in﹣law.MygirlsLaurenandAshleyreadscripturesattheirgrandfather'sfuneral.Ifeelsoproudofthem.MayheRIP.ThemotherofthreecaptionedaphotoofLaurenandAshley. MayheRIPSharonalsopostedonInstagramspeakingoftheirchildren'supbringing.Sharoncreditedherselfforraisingthemtobecharitableandpublicservants.Itaughtthemeverythingtheyknowabout‘pointsoflight'bytakingthemtosoupkitchensandhomelesssheltersfromthetimetheywere4yearsold.Ididn'twantthemspoiledshesaidreferencingthepublicservicenonprofit﹣PointsofLightforwhichherex﹣husbandservesaschairmanoftheboardofdirectors.Ididthis.Neilwasneveraround.HewasalwaystravelingSharonadded. 1WhywasSharonnotinvitedtoGeorgeH.W.Bush'sfuneral? A.Becauseshedidnotintendtoattend. B.BecauseshewasnotNeil'scurrentwife. C.Becausethecathedralcan'tholdsomanypeople. D.Becauseshewasbusywithherchildren'supbringing. 2HowdidSharonmournforthepassingawayofherformerfather﹣in﹣law? A.Throughmediainterviews. B.Bypostingonasocialmedium. C.Byraisingthreegrandchildren. D.Bylookingbackonlunchingwithhim. 3WhichofthefollowingisTRUEaccordingtothepassage? A.Sharon'smarriagelasted30years. B.NeilandSharonsharethreedaughters. C.PointsofLightisaprofit﹣makingcompany. D.Sharon'sgirlsattendedtheirgrandfather'sfuneral. 4WhatisSharon'sattitudetowardsNeil'sperformanceofbringingupchildren? A.Unconcerned. B.Appreciative. C.Dissatisfied. D.Positive.
BeingoverweightcancausedepressionevenwhennootherhealthproblemsexistaccordingtoastudyreleasedTuesdaybytheUniversityofExeter. Ateam1leadbyresearchersfromtheUniversityofExeteranalyzedUKBiobankdata基因数据库frommore248000peoplewithdepressionand3comparethemtoanothergroupofmorethan290000people. While4haslongbeenknownthatdepressionismorecommoninobesitytheteamconcluded5higherbodymassindex体重指数cancausedepressioninitselfevenintheobese6otherhealthproblems. Ourgeneticanalysisconcludesthatthepsychologicalimpactofbeingobeseislikely7causedepression.Thisisimportanttohelptargeteffortstoreducedepression8makesitmuchharderforpeopletoadopt9healthlifestylehabitssaidDrJessTyrrell.Theteamtestedtheirresultsinmanypeopleandtheyreached10sameconclusionverifyingtheirresults. ThestudyhasbeenpublishedintheInternationalJournalofEpidemiology.
DavidCameronisurgingtoday'syoungsterstoabandonFrenchtoconcentrateonthetongueofthefuture﹣Mandarin普通话. CameronsaidIwantBritainlinkeduptotheworld'sfast﹣growingeconomies.Andthatincludesouryoungpeoplelearningthelanguagestosealtomorrow'sbusinessdeals. BythetimethechildrenborntodayleaveschoolChinaistobetheworld'slargesteconomy.Soit'stimetolookbeyondthetraditionalfocusonFrenchandGermanandgetmanymorechildrenlearningMandarin.TostrengthenhismessagehequotedNelsonMandela﹣theformerpresidentofSouthAfricawhosaidIfyoutalktoamaninalanguageheunderstandsthatgoestohisheadifyoutalktohiminhisownlanguagethatgoestohisheart. CameronsaidthatapartnershipbetweentheBritishCouncil英国文化协会andHanbanwilldoublethenumberofChineselanguageassistantsintheUKby2016andprovideincreasedfundingtoschoolsofofferingMandarinasalanguagechoice.InadevelopmentoftheUK﹣ChinaSchoolPartnershipprogrammefundingwillalsobeprovidedfor60headteacherstomakestudyvisitstoChinain2014. InrecentresearchtheBritishCouncilfoundonly1%oftheadultpopulationspeaksMandarintoalevelthatallowsthemtoconductabasicconversation.Just3000pupilsinEnglandWalesandNorthernIrelandenteredforChineselanguagesGCSEsin2013puttingitfarbehindthetraditionalchoicesofFrenchwith177000Spanishwith91000andGermanwith62000entrants加入者aswellasUrduPolishandArabic. ProfessorDameHelenWallacetheBritishAcademy'sforeignsecretarysaidalackofqualifiedteacherscouldbeabarriertoimproveitspopularity. LauraChanoneoftheco﹣foundersofabilingualMandarin﹣Englishprimaryschoolsaidtheprimeminister'sannouncementwasgoodnewsforthestatusofMandarin.ShesaidIt'sagreathelp.Itwillincreasepeople'sawarenessofMandarinasalanguagetheycanlearn. 1Whatisthetextmainlytalkingabout? A.ThecooperationisimportantbetweentheUKandChina. B.DavidCameronhasvisitedChinaforthreedays. C.ChineselanguageisverypopularwithBritishpeople. D.DavidCameroncallsforBritishstudentstolearnMandarin. 2WhydoesDavidCameronurgestudentstolearnChinese? A.BecauseChinesewillbeawidely﹣usedlanguageintheworld. B.BecausehethinksChinawillbecomethelargesteconomy. C.BecausetherearemanyChinesepeoplelivinginBritain. D.BecauseonlyafewofBritishpeoplecancommunicateinChinese. 3WhatisthepurposeofDavidCameronbyquotingMandela'swordsinParagraph3? A.Tocomparedifferentideas. B.Toshowhisrichknowledge. C.TopersuadepeopletolearnMandarin. D.ToshareMandela'sopinion.
已知集合A＝{x∈N|1≤x≤3}B＝{2345}则A∪B＝
Whenyouaresittinginclasshaveyoueverdrawnpicturesinthemargins页边的空白处ofyournotebooks?Ifsoyouaredoodling.Manypeoplethinkofdoodlingasadistraction分心frommoreimportantthings.Butitmightbejusttheopposite. Onestudyshowsthatdoodlingmayhelpyourememberthingsyouhear29%more.Besidesdoodlingcanhelpyouthinkcreatively.Walkingawayfromaproblemtodrawmightactuallyhelpyousolveit.Whenyoucomebackyou'llhaveafreshperspectiveandfigureoutananswermorequickly. AnauthornamedSunniBrownwroteabookondoodling.Shearguesthatdoodlingisatoolthatcanhelppeoplethink.Infactsherunsabusinessthathelpscompaniesimproveorganizationandplanningthroughdoodling.Brownbelievesdoodlingishelpfulbecauseitincludesmanywaysoflearning.Youlearninfourwaysseeinghearingreadingorwritingandthroughmovement.Themorewaysyouusethebetteryoulearn.Andwhenyoudoodlewhilelisteningtoalectureyouuseallfour. Youmightthinkthatbeinggoodatdrawingisimportantfordoodling.Butifthepointofdoodlingistohelpyouthinkthenitdoesn'tmatterwhatthepicturelookslike.Evenifyou'renotanartistdoodlingcanhelpyou.Sonexttimeyouneedhelpfocusingpickupapenanddoodleaway! 1Thepassagemainlytellsustheofdoodling. A.advantages B.disadvantages C.effects D.problems 2WhatdoestheunderlinedwordperspectiveprobablymeaninParagraph2? A.体验 B.观点 C.困扰 D.机会 3HowdoesSunniBrownfeelaboutdoodling? A.Ithelpsrememberbetter. B.Ithelpsthinkcreatively. C.Itinvolvesfourwaysoflearning. D.Itneedsdrawingskills. 4Accordingtothetextitishelpfultodoodlewhen. A.youwanttofocusyourattention. B.youhaveaconversation. C.youwonderinthepark. D.youwatchamovie. 5Whereisthepassagepossiblytakenfrom? A.Abookreview. B.Amessageboard. C.Astudenttextbook. D.Asciencemagazine.
Let'scatchaglimpseofthelatestinventionsthisyear. Parallelsletsyouusedesktopappsonyourphone You'dthinkmostapplicationswouldhavecreatedamobileappbynow﹣butmanycompaniesstillusedesktopappsexclusively.NowParallelsAccessletsyouaccessthemonyoursmartphone.AllyouneedtodoisdownloadtheappthenconnectParallels'Applification™toyourcomputersoyoucanaccessimportantfilesandotherappswithasingleclick.Youcaneasilyuseyourappsinfull﹣screenmodeusingintuitive直观的touchcontrolstoworkfasterthanbefore. UsuallyParallelsAccessis﹩19.99butyoucangetitnowfor﹩9.99. Takeyourlightingtothenextlevelwiththissmartswitch Youprobablydon'tspendalotoftimethinkingaboutyourhome'slightingbutit'simportantthewaythatyoucontrolyourlightingaffectstheenvironmentandyourelectricbill. ThisWiFiwallswitchiscontrolledviaacompanionapponyoursmartphonesoyoucancontrolconnectedlightsorceilingfansfromanywhere. UsuallytheMerossWiFiWallLightSwitchcosts﹩45.99butrightnowit'sonsalefor﹩39.99. Shootbeautifullyclearvideoswiththissmartphonegimbal Ifyou'reinterestedinshootingprofessional﹣qualityvideosandphotosyoudon'thavetospendafortunetotakeabeautifullycomposedshotjustusethisRigietSmartphoneGimbalinstead. Agimbalisasupportforyourcamerainthiscaseyoursmartphonethatallowsittopivot移动andautomaticallydetectandadjusttothepositionthatyouwanttofilmin.Unlikeanyothercamerahardwareyoumightownthisonecomeswithitsownaccompanyingapp. UsuallythisRigietSmartphoneGimbalis﹩269butyoucangetitnowfor﹩109.99. 1Whatdotheseproductshaveincommon? A.Theysaveusenergy. B.Theymakeusworkfasterthanbefore. C.Theymakeourlifeeasierandmorecomfortable. D.Wehavetodownloadtheirappsbeforetheyareused. 2Whichproductgivesyouthebestdiscount? A.TheRigietSmartphoneGimbal. B.TheMerossWiFiWallLightSwitch. C..TheParallelsAccess. D.TheDesktopApps. 3Inwhichsectioncanweseethearticleinanewspaper? A.Education. B.Science. C.Society. D.Culture.
执行如图所示的程序框图若输入的S＝12则输出的S＝
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