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如图，在x＞0的区域存在方向垂直向里的匀强磁场，在x＜0的区域紧挨着y轴有对平行的金属板，金属板中线与x轴重合，板长为L，板间距离为d，两板间电压为U．两个正粒子a和b先后以v和2v从极板左边缘中间...
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高三下学期物理《》真题及答案
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如图所示在x＜0的区域内存在沿y轴负方向的匀强电场在第一象限倾斜直线OM的下方和第四象限内存在垂直纸
在图中实线框所示的区域内同时存在着匀强磁场和匀强电场.一个带电粒子不计重力恰好能沿直线MN从左至右通
匀强磁场方向竖直向上，匀强电场方向垂直于纸面向外
匀强磁场方向竖直向上，匀强电场方向垂直于纸面向里
匀强磁场方向垂直于纸面向里，匀强电场方向竖直向上
匀强磁场和匀强电场的方向都水平向右
如图所示在x>0的区域内存在着垂直于x0y平面的匀强磁场B磁场的左边界为x=0一个带电量为q=+1.
如图POy区域内有沿y轴正方向的匀强电场POx区域内有垂直纸面向里的匀强磁场OP与x轴成θ角.不计重
在某一真空空间内建立xOy坐标系从原点O处向第I象限发射一荷质比的带正电的粒子重力不计.速度大小v0
如图所示在区域I0≤x≤3dy＞0内存在着垂直xOy平面向外的匀强磁场磁感应强度大小为2B在区域Ⅱ0
a粒子在区域I
如图所示在x
14分某科研小组的隐形技术可等效为下面的模型如图所示在y>0的区域内有一束平行的α粒子流质量设为M.
如图所示在x轴上方有水平向左的匀强电场电场强度为E在x轴下方有垂直于纸面向里的匀强磁场磁感应强度为B
如图所示在x轴上方y轴右方的区域中存在匀强磁场磁场方向垂直于纸面向里磁感应强度大小为B.一个带电粒子
如图所示在平面直角坐标系中有一个垂直于纸面向里的圆形匀强磁场其边界过原点O.和y轴上的点a0L.一质
如图所示在xOy平面内第Ⅲ象限内的直线OM是电场与磁场的边界OM与负x轴成45°角.在x＜0且OM的
如图甲所示直角坐标系中直线AB与横轴x夹角∠BAO=30°AO长为a假设在点A.处有一放射源可沿∠B
在xoy坐标平面内存在着如图所示的有理想边界的匀强电场和匀强磁场在x
在xoy坐标平面内存在着如图所示的有理想边界的匀强电场和匀强磁场在x
如图22所示在x＜0且y＜0的区域内存在垂直纸面向里的匀强磁场磁感应强度B.大小为2×10-4T在x
如图所示在x
如图所示在直角坐标系xoy的第一四象限区域内存在两个有界的匀强磁场垂直纸面向外的匀强磁场Ⅰ垂直纸面向
如图所示在x
如图所示在x＜0且y＜0的区域内存在垂直纸面向里的匀强磁场磁感应强度大小为B.在x＞且y＜0的区域内
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保护生物多样性是实现人类社会可持续发展的基础相关叙述错误的是
下列关于胚胎移植的叙述错误的是
下列各组实验中实验材料的选择及理由均正确的是
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
据测算我国每天因土地沙漠化造成的经济损失约1.5亿元若一年按365天计算我国每年因土地沙漠化造成的经济损失约为多少元结果用科学记数法表示
下列关于生态系统稳定性的叙述正确的是
如图表示真核生物体内碳元素部分转移途径其中AB代表物质①～⑥代表生理过程．相关叙述正确的是
利用科学记数法表示的数原来各是什么数1.732×10²=
科研人员利用图1所示固定化乳糖酶反应装置降解牛奶中的乳糖并研究了乳糖酶凝胶珠颗粒大小对降解效果的影响．实验时将3种不同大小的凝胶珠分别放在反应柱中打开活栓然后以相同的速度向每个反应柱中加入等量的牛奶测定收集的牛奶中葡萄糖的浓度结果如图2．请回答 1乳糖酶催化乳糖降解为葡萄糖和． 2制备固定化乳糖酶凝胶珠时溶解海藻酸钠宜采用的方法．应用溶液浸泡凝胶珠使其形成稳定结构． 3与固定化细胞相比固定化酶时使用的海藻酸钠浓度应适当这样可以减少． 4本实验结果表明直径为mm的乳糖酶凝胶珠降解乳糖的效果较好分析其原因是． 5在凝胶珠颗粒直径一定时控制牛奶流经反应柱的速度测定不同流速下收集的牛奶中葡萄糖浓度．请在相应位置的坐标中绘制收集的牛奶中葡萄糖浓度相对值与流速之间的关系曲线．
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．
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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