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如图甲为一列简谐横波在某一时刻的波形图，图乙为介质中x＝2m处的质点P，以此时刻为计时起点的振动图象．Q点是平衡位置在x＝0.5m处的一个质点． ①判断波的传播方向并算出波速大小； ②求Q点从此...
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高三下学期物理《》真题及答案
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图甲为一列简谐横波在某一时刻的波形图图乙为质点P.以此时刻为计时起点的振动图象从该时刻起
经过0.35 s时，质点Q.距平衡位置的距离等于质点P.距平衡位置的距离
经过0.25 s时，质点Q.的加速度大于质点P.的加速度
经过0.15 s，波沿x轴的正方向传播了3 m
经过0.1 s时，质点Q.的运动方向沿y轴正方向
一列简谐横波在某一时刻的波形图如图甲所示图中P.Q.两质点的横坐标分别为x=1.5m和x=4.5m.
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①④
②③
②④
图甲为一列简谐横波在某一时刻的波形图图乙为介质中x=2m处的质点P以此时刻为计时起点的振动图象．下列
一列简谐横波沿x轴传播如图所示实线为t＝0时刻的波形图虚线表示经过Δt＝0.2s后的波形图.1求波速
如图所示一列简谐横波沿x轴传播实线为t1＝0时刻的波形图虚线为t2＝0.25s时刻的波形图已知这列波
2m/s，向左
2m/s，向右
6m/s，向左
6m/s，向右
图甲是一列沿x轴正方向传播的简谐横波在t=0时刻的波形图此时离原点6m的介质质点刚要开始振动图乙是该
波长为4m
周期为3s
传播速度为2m／s
波源起振方向向上
图甲为一列简谐横波在t=0时刻的波形图图乙为质点P.以此时刻为计时起点的振动图象1简谐横波的传播方向
一列沿x轴传播的简谐横波某时刻的波形图象如图中的实线所示再经t=0.2s的波形图如图11中的虚线所示
一简谐横波在某一时刻的波形图如图甲所示图乙为介质中x=2m处的质点P.以此时刻为计时起点的振动图象则
图1为一列向左传播的简谐横波在某一时刻的波形图判断波形图上P点的振动方向.
如图甲所示是一列沿x轴正方向传播的简谐横波在t=0时刻的波形图P.是离原点x1=2m的一个介质质点Q
这列波的波长为λ = 4 m
这列波的周期为T. = 3 s
这列波的传播速度为v = 2 m/s
这列波的波源起振方向为向下 E.乙图可能是图甲中质点P.的振动图像
图甲为一列简谐横波在某一时刻的波形图.ab两质点的横坐标分别为x=2m和x=6m图乙为质点b从该时刻
该波沿+x方向传播，波速为1m/s
质点a经4s振动的路程为4m
此时刻质点a的速度沿+y方向
质点a在t =2 s时速度为零
图甲为一列沿x轴正方向传播的简谐横波在t=0时刻的波形图P.是离原点x1=2m的质点Q.是离原点x2
这列波的波长λ=6 m
这列波的波速v=3 m/s
这列波的波源起振方向为向上
图乙可能是图甲中质点Q.的振动图象
在图中实线是0时刻一列简谐横波的波形图虚线是0.2s时该波的波形图求这列波的周期和波速
一列简谐横波如图所示波长λ＝8m实线表示t1=0时刻的波形图虚线表示t2=0.005s时刻第一次出现
一列沿x轴传播的简谐横波某时刻的波形图象如图中的实线所示再经t=0.2s的波形图如图中的虚线所示.则
细绳的一端在外力作用下从t=0时刻开始做简谐运动激发出一列简谐横波在细绳上选取15个点图1为t=0时
如图所示是一列简谐横波在t1=0时刻的波形图已知这列波沿x轴正方向传播波速为20m/s试画出t2＝0
如图甲为一列简谐横波在某一时刻的波形图图乙为介质中x=2m处的质点P.以此时刻为计时起点的振动图象.
这列波的传播速度是20m/s
经过0.15s，质点P.沿x轴的正方向传播了3m
经过0.1s时，质点Q.的运动方向沿y轴正方向
经过0.35s时，质点Q.距平衡位置的距离小于质点P.距平衡位置的距离
图甲为一列简谐横波在某一时刻的波形图ab两质点的横坐标分别为和图乙为质点b从该时刻开始计时的振动图象
该波沿+x方向传播，波速为1m/s
质点a经过4s振动的路程为4m
此时刻质点a的速度沿+y方向
质点a在t=2s时速度为零
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There'snodoubt﹣thatlearningaforeignlanguageisdifficultandwhenitcomestospeakinginthelanguageitcanberatherterrifying.Irememberwalkingintomyfirst﹣everSpanishclassatuniversityonlytodiscoverthathalfofmyclassmateswerealreadyfluentinseverallanguages.1 AtfirstthethoughtofspeakinginSpanishterrifiedme;notonlyweremyvocabularyandgrammarverylimitedbutIhadneverspokenanotherlanguagebefore.ButIwasdeterminedtoovercomemyfearandbyemployingafewsimplestrategies策略Ihavebeenabletobuildmyconfidenceanddevelopatmyownpace.2 FirstlyrememberitisOKtomakemistakesandthatyoushouldfacethem3Butwhenitcomestolanguagelearningweoftenaimforperfectionandfeelasthoughwearenotreadytospeakuntilwehaveenoughwordsorgrammaticalknowledge.Thetruthisthatyouwillneverfeelreadyandinsteaditisimportanttousetheknowledgethatyoudohavetocommunicatewhatyoucan. Thisleadsontomynexttip:4Thiscanbeahardoneespeciallyifyouareinalargelanguageclass.Itisimportanttorememberthatwealllearnatdifferentspeedsandthroughdifferentstylesoflearning.Byallmeanskeepupwithyourclassmaterialbutdonotworryifyoudon'tunderstandeverything﹣especiallyintheearlystages. Lastlycelebratethesmallsuccessesandrememberhowfaryouhavecome!5Soinsteadoffocusingonhowforyouhavetogofocusontheprogressyouhavealreadymadeandbeproudofyourachievements! A.Thissoundsobvious. B.It'shardlydifficulttodoso. C.Ifeltitwasreallyoutofmyreach. D.Don'tcompareyourselfwithothers. E.Trytokeepupwithotherclassmates. F.Afteralleverytinysuccessandlittleprogressisworthcheeringfor. G.SoIwillshareafewtipswithyouhopingthatyoufindthemusefultoo.
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为研究低温对某种热带植物叶绿体结构和代谢的影响科研人员选用长势一致的两个品种的幼苗分别在28℃和0℃条件下处理一段时间后测定幼苗叶片离体叶绿体的放氧量和叶绿体中MDA含量MDA是膜脂质分子过氧化产物其含量反映叶绿体膜的受损程度结果如图．请回答 1测定离体叶绿体放氧量实验中需要控制的无关变量有至少两项． 2离体叶绿体中放氧的场所是与氧气同时产生的物质将进入直接参与过程． 3根据实验结果分析叶绿体中MDA含量与膜受损程度呈填“正”或“负”相关．低温胁迫引起放氧量下降的原因是使叶绿体中色素含量． 4本研究表明两个品种中较耐低温的是．
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处错误每句中最多有两处每处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:在错的词下面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. Idon'tknowwhattoexpressmysincereapologytoJimbecauseIlostthebookhelentittome.Iwasverygratefulwhenheputabookonmydesk.InordertogiveitbacktohersoonIspentthreedaysreadit.ThenextdayItookthebooktoJim'sclassroomtoreturnit.LuckilyIcouldn'tfinditanywherewhenIarrivedathisclassroom.TherewasobviousthatIcouldn'tgiveitbacktohimasIpromisedbefore.WhatshouldIdonow?Idecidetobuyanewonetohimandwritealetterofapologytohim.ThelessonformeisthatIshouldtakegoodcareofwhatbelongtome.
Doyouwantyourparentstobeproudofyou?Doyouwantthemtotrustyouthemostandbelievethattheycancountonyou?Doyouwanttobetherolemodelofgoodbehavior?Beingresponsibleistheanswer.Thenhowtoberesponsible? 1. Parentslovetoseecleanroomsorganizedclosetsandfloorsthatdon'thavepilesofthingsonthem.Doalittlebitofcleaningeachdaysoitisneveroverwhelming. Trysettingasideatimetodofiveminutesofcleaningsuchasaftersuppereachevening. Dresswellandtakegoodcareofyourbody. Findyourownpersonalstyle:cutepreppygirlyboyishseriousorwhimsical.Whateveryourstyleyourclothesshouldbeneat.Brushyourhairandteethstaycleanand2.Thiswillhelpyoulookandfeellikeanangelchild. Stayontopofyourresponsibilities. Doyourhomeworkassoonasyoucomehomewhichwillpleaseyourparentsandgiveyoutherestofthedayfree.Puteffortintoyourschoolworkandgetthebestgradesyoucan. Ifyouneedhelpaskforit!Thiswon'tbotheryourparents﹣3 Getplentyofsleepeatwellandspendtimeoutdoors.Thisshowsyourparentsthattheytaughtyouwell. Acknowledgeyourmistakes. Blamingotherpeopleisimmatureandparentscanusuallytellwhenyou'redoingit.InsteadgotoyourparentsandsayItwasmyfaultandIamsorry.Evenifthey'reunhappyaboutyourmistake4Butdon'tbackanswertheycansurelygetangryandwouldalwayspointoutyourmistakesthenexttime.Socontrolyourselfandstaycalmeveninthetimeofworstsituations. Keepyourpromises. Ifyouofferedtohelpdowhatyousaidyou'ddo.5andthey'lltrustyouwhenitcomestotheimportantthings.Ifyouaren'tsurewhetheryoucandosomethingdon'tpromisetodoit.InsteadsayIthinkIcanorI'lltry. A.Dowhattheyaskyoutodowithouttalkingback. B.Eatfruitsandvegetable. C.Yourparentswilllovetoseeyoubeingkind. D.Itshowsthemthatyoucare. E.Theywillbeproudofyouforowninguptoit. F.Parentsappreciatereliability. G.Stayneatandorganized
把下列数据用科学记数法表示出来全世界人口约为61亿
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利用科学记数法表示的数原来各是什么数1.732×10²=
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阅读下面短文根据所给情节进行续写使之构成一个完整的故事. Iwasdoingabigclean﹣uprecentlyandmykidswerehelpingwhenmysonFreddocameacrossaknottedhandkerchiefwithanolddarkbrowncoininside.MumcanIhavethis?CanIplaywiththiscoinheasked.Itookonelookandwasimmediatelytransportedtoanothertime. In1991therewasatimewhenmyfriendandIworkedinabackwardAfricancountryNigerhitbysandstormsandburningheat.ThereweremanythingsIfounddifficultaboutthisplace﹣﹣theclimateandbeggarsweremybiggestheadaches.SoafterfinishingfivemonthsofnursingworktherewemovedontoworkatahealthclinicinneighbouringcountryBurkinaFaso.It'smuchgreenerinBurkina.EventheCoketastesbetterthelocalsassuredus. Yetthefactwasquitetheopposite.ArrivingbytaxiatourdestinationinBurkinawebegantounload.Iwasreachingformylargerpieceofluggagewhenoutofthedarknessamotorbikewithtwomenapproachedslowly.Withoutwarningoneofthemengrabbedmydaypackasthemotorbikesweptcloseby.Withinsecondsthepairwereoutofsightswallowedupbythenight. Withmypassportmoneytraveller'schequesallinthebagIwasindeeptrouble.Howfrustrating!AllIwantedwastoleavethishellhole!ThenwalkingthroughBurkina'sstreetsonedayIwasstoppedbyanoldwomanwhothrustherhandinmyface.Cadeau'gift'inFrench!Cadeau!shecried.I'dhadenough!Iwasextremelytiredofthecountry:itspovertyitsthievestheheatthedustand…everything!ItoldherangrilyandfirmlyinFrenchIhaveno'Cadeau'.Ihavenomoney.AthiefstoleallmymoneytwoweeksagoandnowIcan'tgetoutofyourcountry.Icannotgiveyouanything.NOTHING!'Thebeggarwomanlistenedattentively.Tomygreatsurpriseafterhearingmywordsshegaveabroadsmile. 注意:1.所续写的短文的词数应为150词左右; 2.应使用5个以上短文中标有下划线的关键词语; 3.续写部分分为两段每段的开头语已为你写好; 4.续写完成后请用下划线标出你所使用的关键词语. Shereachedintothepocketofherdress. Therewasaslighttouchonmyhand;lookingdownIsawmysonlookingatmecurious.
Whatcouldhomesofthefuturebelike?Nooneknowsexactly.Butpreparationsaremadefortheworld'sfirstfreeform3D﹣printedhouse. ExpertswillbuildahousecalledCurveAppealwhichwillbe3D﹣printedoff﹣sitebeforebeingputtogetheron﹣sitetocreatetwooutsidewallsaroofandaninsidepart.Thesefourmainpartswillthenbejoinedtogether. Although3D﹣printedbuildingshavebeenmadebeforethishome﹣﹣﹣tobebuiltinChattanoogaTennesseelaterthisyear﹣﹣﹣willbethefirstofitskindasitwillcontainnoregularshapesorangles.ThehouseisthecreationofthedesigncompanyWATGbasedinLondonandCalifornia.ThedesignforCurveAppealdrawsinspirationfromtheCaseStudyHouseprogram. Thearchitects建筑师leadingtheprogramwerefamousfortryingtocreateopen﹣planspacethataddsnaturallight.InawrittenstatementaspokesmanforWATGsaidUsingmanyofthesamemoderndesignprinciplesCurveAppealisthenextdevelopingstep.It'simportantthatthebuildingsandtheenvironmentworktogetherharmoniously.ThechosensiteforCurveAppealisstepsawayfromtheTennesseeRiverinabeautifulwoodedsunlitarea. WATGwasawardedthefirstprizeintheFreeformHouseDesignChallengein2016andgivenprizemoneyof﹩8000tomakeitsplansareality.Thecompetitionwasdesignedforarchitectsdesignersengineersandartists. Competitorswerechallengedtodesigna600to800﹣﹩qftsingle﹣familyhomethatrethinkstraditionalaesthetics美学constructionbuildingsystemsandstructure. OverthelastyearWATG'sChicagoofficehasbeendevelopingtheirdesignwithBranchTechnology.Thisprojectwillbecompletedlaterthisyear.OncecompletedtheCurveAppealhomewillhaveopenandlight﹣filledinsidelivingspace. 1WhatcanweknowaboutCurveAppealfromthepassage? A.Itwillbedifferentfromanordinaryhouse. B.Itisthefirst3D﹣printedbuilding. C.Ithasvisiblewallsbutnoroof. D.Itwaseverbuiltintheworld. 2Whereisthefreeform3D﹣printedhouselocatedaccordingtoParagraph4? A.FarawayfromtheTennesseeRiver. B.InthewoodsneartheTennesseeRiver. C.NearWATG'sChicagooffice. D.Nexttosomemodernbuildings. 3WhatdoestheFreeformHouseDesignChallengedo? A.Itinspirespeopletodesignwhattheylike. B.Itonlyacceptsdesignsintraditionalways. C.Itofferscompetitorsinspirationwhennecessary. D.Ithelpsputcreativeideasintopractice. 4What'sthepassagemainlyabout? A.Thedesignofhomesinfuture. B.TheFreeformHouseDesignChallenge. C.Theworld'sfirstfreeform3D﹣printedhouse. D.Thedevelopmentof3D'sprintinginarchitecture.
Twoladieslivinginoppositeapartmentssayhellowhentheymeeteachotherinthecorridor.OneofthemsaysImovedherefiveyearsago1Inevermetyoubefore.CouldIaskyournameplease?TheothersaysI2behereforsixyears.HowshouldIcallyou? Itseemsveryridiculous3peoplelivingsoneardon'tknoweachotherforsuchalongtime.HoweverYoucanfindthiskindofstory4performeverywhere.Itistheexact5reflectofinterpersonalrelationshipsinthemodernworld.Inthemodernworldmostpeopleliveinapartments.Theyclosetheirdoorsandnevergooutassoonastheygethomefromwork.Iftheylivealonetheywillkilltheir6watchingTVorreadingmagazines.Theydon'thaveanyconnectionsevenwiththeir7closeneighborswhoseemnodifferentfrompeopletheymeeteverydayin8street. Thisphenomenonisnogoodtousnortooursociety.Peoplewillfeelmoreandmorelonely.Theworldbecomessoindifferent.It'stimethatwe9takesomemeasurestoimproveit.Peoplelivinginthesameplacecan10organizetohavesomeactivities.Weshouldcallonpeopletobefriendlytoeachother.
Backabout10monthsagoIstartedcollegeandjuststruggledwitheverythingsuchasclassesandfriends.Iquicklybecamedepressed抑郁的andangryatmyselffornotbeingabletodobetterinschoolinadditiontolack缺少offriendsduetopoorsocialandcommunicationskills. Thiswentonformonthsuntilmy19thbirthday.Myparentssentmeagreatcake.ButIabsolutelyhadnoonetoshareit.Ithrewoutthecakeafterhavingonepiecewithabout90%ofitleftover.ThatnightIwasdepressedsoIdecidedtogooutsidetothefreezingtemperatureofthewinterandrun.Iputmyearphonesinandranabout2milesat11p.m.onmybirthday. WhenIgotbackinsideIwasproudofwhatIwasabletodo.ThenextnightIdidthesame.Iwasn'tquickorfitbutIwentoutsideanddidsomething.Therunningcontinuedfor2monthsuntilIfinallyhadcouragetogotothegymwhereIstartedswimmingasIusedtodoinhighschool.AmonthwentbyandIstartedliftingweightandcontinuallyrunning. LookingbackIcanseethatexercisehelpedcure治愈mydepressionbutitdidn'tonlydothat.AtthegymImetnewfriendsandbackatmydormIgrewconfidenttoplaySuperSmashBrotherswithmyclassmates. NowIexerciseforonehourandahalfeverydayandlookforwardtothat.IgetdailytodowhatIlovewithpeoplewholoveitaswell.Ihopethishelpssomeonewhomaybeorhavebeeninasimilarsituation. 1Whatmadetheauthordecidetorunatnight? A.His19thbirthday. B.Hisparents'cake C.Hisloneliness. D.Hisroommates. 2Whichofthefollowingbestdescribestheauthor? A.Determined. B.Humorous. C.Generous. D.Selfless. 3Whatisthebiggestbenefitoftheauthor'srunning? A.Losinghisweight. B.Regaininghisconfidence. C.Playingwithhisparents. D.Joiningotheractivities. 4Whydoyouthinktheauthorwrotethispassage? A.Tointroducehislifeincollege. B.Toshowhisthankstohisparents. C.Toemphasizetheimportanceoffriendship. D.Tosharehisexperienceofdealingwithhardship.
江苏某城市为有效降低污水中的有机物和氮磷含量建立了如图所示的污水综合处理系统厌氧池和阶梯跌水曝气塔的池体填料中含有大量的活性微生物．请回答 1污水排放会引起水体富营养化藻类等浮游生物大量繁殖加之死亡后被微生物分解引起水体的溶解氧下降造成鱼类等死亡进一步破坏了生态系统稳态这种调节机制称为． 2厌氧池中的微生物在生态系统中属于．厌氧池中的微生物降解有机物的能力强原因是． 3设计阶梯跌水曝气塔的优点是污水流经阶梯跌水曝气塔时将其中的NH转化成NO和NO的生物是． 4在相应位置的图解中用箭头补全人工湿地中碳元素的转移途径．
BooksforKids ●LesserSpottedAnimalsbyMartinBrown ImageSource:Scholastic Haveyoueverheardofanumbat食蚁兽ordzorilla非洲艾鼬?Noneitherhadwe.Thankstothisunusualpicturebookbothyouandyourlittleanimalloverscanlearnaboutawholegroupofnewcreatures.Beware:Youmaystartaskingforforeignpetsafterturningthesepages. AvailablefromAmazon＄14.47 ●HowtoAvoidExtinctionbyPaulPaulAcampora ImageSource:Scholastic YourmiddleschoolerwillcertainlyenjoyjumpingintoanoldBuickalongwithLeohis16﹣year﹣oldcousinandalovelydognamedKermitonacross﹣countryroadtrip.Thisfuncomedicbookfilledwithfoodfamilyandfossilswillteachkidsaboutlifeinawaytheycangrasp.Ifyou'relookingforagoodreadforyourkidsthisisit. AvailablefromAmazon＄8.95 ●What'sOutThere?byLynnWilson ImageSource:PenguinRandomHouse DoyouhaveaCuriousAstronaut﹣wannabeonyourhands?ThisclassicReadingRailroadbookwillteachyourchildwhatthesunismadeofwhatcausesthemoontochangeshapeandallabouttheplanetsinjustafewpages.Thisbookissimplyoutofthisworld. AvailablefromAmazon＄3.99 ●ScienceStunts:Fun.FeatsofPhysicsbyJordanD.Brown ImageSource:PenguinRandomHouse Doesyourlittlescientistalsolovemagic?We'vefoundtheperfectbookforthem!They'llbeshockedbythewaythesesimplemagictrickscancometogetherwiththehelpofabitofscience.Thisisonebookthatwillhaveyousmilingfromeartoear. AvailablefromAmazon＄12.59 1Peterwhoisananimalfanmaylikeread. A.LesserSpottedAnimals B.HowtoAvoidExtinction C.What'sOutThere? D.ScienceStunts:Fun.FeatsofPhysics 2WhatcanchildrenlearnfromthebookWhat'sOutThere? A.Funofscience. B.Extinctionofspecies. C.Knowledgeoftheuniverse. D.Experienceofaforeigntour. 3Whichbookmaymakechildrenburstintolaughter? A.What'sOutThere? B.LesserSpottedAnimals C.HowtoAvoidExtinction D.ScienceStunts:Fun.FeatsofPhysics
LONDON﹣BritainpreparesforavoteThursdaythatwilldecidewhetheritleavestheEuropeanUnion.Thedebatehascenteredonimmigrationandeconomicsecurity.Bothsideshaveloweredthetoneoftheirargumentsafterathree﹣daysuspension暂停ofcampaigningthatfollowedthemurderofananti﹣Brexitlawmakeranincidentthatpolls民意调查suggesthasshockedmanypreviouslyundecidedvoterswhonowsaytheywillvotetoremain. TheseareuncertaintimesinanationwhoseeconomyisthesecondlargestintheEuropeanUnion.Therisksarehuge.Therearewarningsthatleavingthe28﹣membergroupmaycausetheBritishpoundtolose15percentofitsvalueandbringtheresignation辞职ofDavidCameronthecountry'sprimeminister;hisstayornotdependsonwhetherBritainlistenstohimandvotestoremain. FormonthstheLeavecampaignhasbeenhittingthestreets.Itsargumentsarebasedlargelyon immigrationandthebeliefthatBritainhashandedcontrolofitsborders边界toaEuropeansuperstate:TheU.K.haslostcontrolovermigration.WehavetoacceptanyoneintothiscountryiftheyhaveanEUpassportnomatteriftheyhaveacriminalrecordornot.Wearenotallowedtosay'no'topeopleandthatisdamagingforthesecurityoftheU.K.butitisalsoputtingpressureonjobsandopportunitiesforyoungpeoplesaidTomHarwoodaBrexitcampaigner. ThemurderofJoCoxananti﹣Brexitpro﹣immigrantlawmakerbyafarrightextremist极端分子withahistoryofmentalproblemshadaseriouseffectonbothcampaignsandonvoters. PollssincetheJune16thmurdershowedtheLeavecamplosinggroundbutwithbothsidesstillverycloseonareferendum全民投票thatmanybelievecouldchangethecourseofEuropeanhistory. 1WhatdoestheunderlinedwordBrexitinparagraph3mean?. A.BreakthelawoftheEuropeanUnion. B.BreakawayfromtheEuropeanUnion. C.BuildtheexittotheEuropeanUnion. D.BantheimmigrationintoBritain. 2Whatisimpliedfromthepassage? A.TheimmigrationhascausedgreatconcerninBritain. B.BrexitwillbegoodforBritisheconomy. C.Bothcampshavebeencampaigninganddebatingonthestreetsformonths. D.ThemurderofJoCoxmademanyvotersdeterminedtovotefortheexit. 3Whichofthefollowingstatementistrue? A.BritainwillleavetheEuropeanUnionafterthevote. B.AnyonewithapassportcanchoosetostayandworkinBritain. C.WhetherCameronwillresigndependsontheresultofthereferendum. D.JoCoxwasmurderedbyaBrexitcampaignerinJune16m. 4What'stheattitudeofthereporttotheeventofBrexit? A.Positive B.Negative C.Indifferent漠不关心的 D.Concerned
下列关于人体神经递质的叙述正确的是
Myfirstlessonwasatameeting.AswesettledaroundthetableIheardMegwhowas1arecentoperationtalkingtoJudiththemanagerofourprojectThankyousomuchfor2mydaughterstotheirdancelessonlastweek.Don'tmentionitJudithsaidItwasnothing. Knowinghow3JudithwaswithherworkkidsandagingparentsIfoundherdrivingMeg'schildrentodancelessonsunbelievably4. IwasabouttosaymoreaboutthiswhenDonnaanothercolleagueenteredtheroom5. Sheapologizedforbeinglatesayingshejusthadhostedalunchforherfriendswhowereoverseventy.ThatwassoniceofyouIsaid6howshedidn'tliketocookorclean.Ohshesaidwavingher7Itwasnothing.SomehowIcouldstilltellthe8inhervoice.Shegainedasenseofsatisfactionfromtheentertainment款待offeredtoherfriends. Seeingtheir9tohelpothersselflesslyIstartedthinkingabouttheconceptofnothingthispeacefulandgenerouswayofliving﹣﹣﹣wasitreallynothingorweretheysimplysayingthat?Isuddenly10thatonceIspentawholeafternoonafterworkhelpingafriend11aspeechshewasgoingtodeliver.I12hertorearrange重新安排theorderofthestoriesinthelecturetomakeitsoundmore13.Afterthefifthtryshefinally14it.Shehuggedmewith15sayingthankstome.Ismiledandsaiditwasnothing. SuddenlyIrealizedthathelpingsomeonewasreallysomethingtome.Ilearntthatgivingfromtheheartdoesn't16meanhardwork.The17isfindingsomethingwelovetodoandfindingsomeonewho18thatsomething.Ourgenerositycan19othersaswellasourselves.Onceyouhaveagood20ofitit'snothing.Andit'sreallysomething. 1A.recoveringfrom B.adaptingto C.goingthrough D.joiningin 2A.guiding B.fetching C.driving D.dragging 3A.common B.busy C.strange D.practical 4A.frightened B.sincere C.gifted D.generous 5A.hurriedly B.disappointedly C.angrily D.unexpectedly 6A.ignoring B.knowing C.forgetting D.predicting 7A.eyes B.feet C.leg D.hand 8A.pleasure B.sadness C.surprise D.regret 9A.progress B.adventure C.promise D.willingness 10A.referred B.refused C.remembered D.respected 11A.preparefor B.putup C.giveaway D.takeapart 12A.begged B.invited C.advised D.permitted 13A.unbelievable B.reasonable C.sensitive D.puzzling 14A.got B.meant C.caught D.made 15A.concern B.worry C.gratitude D.apology 16A.normally B.accidentally C.necessarily D.possibly 17A.treat B.trick C.belief D.plan 18A.needs B.admires C.loves D.defends 19A.defeat B.benefit C.win D.regard 20A.order B.balance C.impression D.command
杜氏肌营养不良症一般在3～5岁时开始发病20～30岁因呼吸衰竭而死亡受一对等位基因Dd控制．亨廷顿舞蹈症一般在中年发病受另一对等位基因Hh控制．如图是某家族两种遗传病系谱图其中Ⅰ3不携带致病基因．请回答 1利用DNA分子杂交技术鉴定Ⅰ3是否携带致病基因的原理是． 2该家族中杜氏肌营养不良症和亨廷顿舞蹈症的遗传方式分别是． 3Ⅰ4的基因型是．Ⅱ3产生同时含有两种致病基因卵细胞的概率是． 4Ⅲ3患杜氏肌营养不良症的概率是． 5若Ⅲ2与一正常男性婚配生一男孩该男孩正常的概率是．
利用科学记数法表示的数原来各是什么数-5.002×104＝
Fishingisapopularactivityandeveryfishermanknowstherule:Keepthebigonesthrowthesmalleronesback.Theideabehinditissimple﹣thelargerfishareprobablyolder.Ifyoukeepthesmalleronestheywon'tbeabletoreproduceandthefishpopulationwillbeindanger. Butfishingoutthelargestfishfromapopulationhasanunwantedeffect:Overtimefeweradultfishgetreallybig.Ifonlythesmallerfishreproducethenfuturegenerationswillbecomesmaller.Thisisanexampleofevolution进化inaction. OnescientistDr.DavidConoverhasspentthelastdecadestudyingtheeffectsofthekeepthebigonesruleandiftheycanbechanged. TosetuphisexperimentConoverandhisteamcaughthundredsofsilversidefishanddividedthemintosixgroups.FortwogroupsConoverfollowedtheukeepthelargeonesruleandtookoutthebiggestfish.Fortwoothergroupsheremovedonlythesmallfish.Forthelasttwogroupsheremovedfishatrandom随意的. Afterfiveyearshemeasuredthefishineachgroup.Inthetwogroupswherethelargestfishwereregularlyremovedtheaveragefishsizewassmallerthantheaveragesizeintheothergroups.Herewastheevolutioninaction:Ifonlysmallfishsurvivetoreproducethenfuturegenerationsoffishwillalsotendtobesmall. ForthesecondfiveyearsofhisexperimentConoverchangedtherulesandtookfishrandomlyfromeachgroup.Attheendoftheexperimenthefoundthatthefishthatwereinthekeepthelargeonesgroupforthefirstfiveyearshadstartedtogetlargeragainalthoughhecalculateditwouldtakeatleast12yearsforthefishinthatgrouptoreturntotheiroriginalsize. Inotherwordsittakeslesstimetoshrinkthanitdoestorecover. 1What'sthetraditionalruleinfishing? A.Keepbothbigandsmallones. B.Keepbigonesandfreesmallones. C.Keepsmallonesandthrowbigonesback. D.Keeptheonesthatcanreproduce. 2DavidConoverdidexperimentonfishinginorderto. A.findpracticalrulesinfishing B.provethetraditionalfishingrulewasreasonable C.seekforgoodfishestoreproduce D.findgoodmethodinraisingsilversidefish 3WhatdidDavidConoversexperimentprove? A.Fishermanshouldfishatcertaintime. B.Fishermanshouldkeepbigonesandfreesmallone. C.Fishermanshouldkeepsmallonesandthrowbigonesback. D.Fishermanshouldkeepfishatrandom. 4Whatdoestheunderlinedwordshrinkmeaninthelastparagraph? A.Becomesmaller. B.Becomeill. C.Becomeweaker. D.Becomeless.
ThefirstMondayinSeptemberisLaborDayintheUnitedStates.Thenationalholidaybeganmorethan100yearsago1honorlow﹣paidfactoryworkers. LaborDayalso2informalmarkstheendofsummer.ManystudentsreturntoschoolafterLaborDay.Thehotdaysofsummerturn3cool.ManyAmericanscelebratetheholiday4anoutdoorfamilybarbecue. ButLaborDaystartedwithastruggle.OnMay1st1889workersdemonstrated游行onthestreetsofParisFrance.InternationalLaborDaywasborn.Mostindustrialized5countryintheworld﹣excepttheUnited StatesandCanada﹣﹣celebrateLaborDayonthefirstofMay. ThefirstAmericanLaborDaycelebration6holdonSeptember5th1882inNewYorkCity.About10000workersmarchedthroughthestreetstoshowthe7strongoflabororganizations. FormanyyearsafterthatAmericanworkersusedthefirstMondayinSeptembertodemandbetterworkingconditionsandpay.Musicwasapartofmanyofthosemarchesandmanylaborsongstraditionallytellstoriesofconflictandhopesfor8betterlife.HereareWeShallNotBeMoved.WhichSideAreYouOn?BreadandRoses. EventhoughLaborDaydemonstrationsarenot9commonastheyareintheU.S.thesongremindsustocelebratetheeffortandlovethatmanypeoplegiveto10theywork.
Youmayfinditexcitingtogetapart﹣timejobduringthesummervacation.1Whenyougetaninvitationtoajobinterviewyouarehalfwaytowardsyourgoal﹣﹣ajoboffer.Hereareafewthingsyoushoulddoafterwards. Respondtotheinvitationtotheinterview.Thankthesenderfortheirtimeandfortheopportunitytoorganizetheinterviewconfirmingthatyouwillbeavailableatthedeterminedtime.2. 3Youneedtodosomeresearchonthecompanyandlearnasmuchaboutthecompanyaspossiblebeforetheinterview.Usethecompany'swebsiteandnewspaperarticlestogatherasmuchinformationaspossible.Youshouldalsobereadytotalkindepthaboutthecompanyandthepositionyouareapplyingfor. 4It'sbesttoprepareforawidevarietyofquestionsbythinkingaboutyourowncareergoalsandsoon.Wheredoyouseeyourselfinfiveyears?isacommonquestion.Workingdiligentlyforyouofcourse!Butunlessyouareactuallytryingtogetajobinyourchosencareerthisprobablyisn'tagoodanswer. Practicewithafriend.5Notonlywillthisgiveyouawaytostructureyourpreparationbutitwillalsohelpyougetcomfortablewithgivinganswers.Practicegivingconcisecompleteanswersandmaintainingeyecontactwiththeinterviewerswhileyougivethem. A.Askpeoplearoundyouforhelp. B.Ifyouhaveafriendwhoisalsopreparingforaninterviewconsiderpreparingtogether. C.Ifyouneedmoreinformationabouttheinterviewthisisthetimetoask. D.Butdoyouknowhowtoprepareforajobinterview? E.Thinkaboutquestionstheinterviewerislikelytoask. F.Whatarethechancesforprofessionalgrowthinthisjobopportunity. G.Doyourhomework.
利用科学记数法表示的数原来各是什么数2×105=
科学家构建了含有大洋鳕鱼抗冻蛋白基因启动子和大鳞鲑鱼生长激素基因的表达载体并将其导入了大西洋鲑的细胞中获得了生长速度加快的转基因大西洋鲑．相关叙述正确的是
把下列数据用科学记数法表法出来地球上煤的储量估计为15万亿吨以上．
Ittakesabigbrain﹣ahumanbrain﹣todomath.Orsoyoumightthink.Butscientistshavefoundthatotheranimalssuchaschimpanzeesmonkeysandevenpigeonscandosomeadditionandsubtraction减法.Nownewresearchshowsthathoneybees﹣withbrainsthesizeofsesameseeds﹣candobasicmath. Researchersputhoneybeesthrough100trialstotrainthemtoaddandsubtract.TheyfirstputthebeesinaY﹣shapedmaze迷宫andpresentedthemwithacertainnumberofeitheryelloworblueshapes.Yellowshowedthebeesshouldsubtractwhilebluemeanttheyshouldadd. Thebeesthenenteredthedecisionroomwheretheywerepresentedwithacorrectanswerononesideandanincorrectanswerontheotherside.Iftheypickedtherightanswertheywererewardedwithasugarydrink.Ifnottheygotbitterwater.Theresearchersalsoputthebeesthroughanothertesttrialwithoutarewardorpunishmenttomakesurethereweren'tanysmellmarksinfluencingthebees'choices. Atfirstthebeespickedanswersrandomly随意地.Youseethattheabilityofthebeestodoitstartsataboutchancelevel50%showingusthebeesarejustchoosingatrandom.Overtimetheirabilitycomesuptoabout80%sotheyactuallystarttoperformquitewell. ScarlettHowardoneofthestudyauthorsandaresearcheratPaulSabatierUniversityinFrancesaysthebeeswereevenabletoaddandsubtractcorrectlywhenpresentedwithanumbertheyhadneverseenbefore.ThestudyisinthejournalScienceAdvances.Thingslikethisletusknowthere'realotofmysteriestobeexploredthereandtheirbrainsmightnotbeassimplisticasweoncethought.Howardadded. 1thetesttrialonhoneybeeswithoutarewardorpunishmentwasdone. A.tohelpimprovetheircalculatingskills B.toavoidsmells'influenceontheirchoices C.toshowtheimportanceofarewardtothem D.toincreasethechanceleveloftheircorrectanswers 2Whatcanbelearnedfromthelastparagraph? A.Honeybeescanonlyworkoutnumberstaughtbefore. B.Alotofmysteriesabouthoneybeeshavebeensolved. C.Thebrainsizeofhoneybeesdeterminestheircalculatingability. D.Thepowerofhoneybeesbrainsmaygobeyondourexpectations. 3Whatistheauthor'spurposeinwritingthetext? A.Topresenthoneybees'abilitytoperformbasicmath. B.Topersuadepeopletoexploremoreabouthoneybees. C.Todiscusshowhoneybeesrecognizeunfamiliarnumbers. D.Toexplainwhyhoneybeesaresmarterthanotheranimals.
假定你是李华你在某贴吧上看到美国孔子学院ConfuciusInstitute的学生Henry发帖希望通过网络视频互动学习中国诗词.请你给他写封邮件内容包括: 1.表示愿意帮助他; 2.说明你想帮助他的原因. 注意: 1.词数100左右; 2.可以适当增加细节以使行文连贯.
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