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如图所示,三棱锥S﹣ABC中,平面SAB⊥平面ABC,平面SAC⊥平面ABC,D,E分别是AB和BC边上的点,且DE⊥AB,SA=2,AD=,DE=1,AC=2,∠AEC=60°,F为CE的中点. ...
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高三下学期数学《》真题及答案
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如图在三棱锥P-ABC中平面PBC⊥平面ABC.若过点A.作直线l⊥平面ABC求证l∥平面PBC.
如图在四边形ABCD中AD∥BCAD=AB∠BCD=45°∠BAD=90°.将△ADB沿BD折起使平
-BCD.则在三棱锥A.-BCD中,下列命题正确的是( )
A.平面ADC⊥平面ABC
平面ADC⊥平面BDC
平面ABC⊥平面BDC
平面ABD⊥平面ABC
已知三棱锥SABC的三视图如图K.381所示.在原三棱锥中给出下列结论①BC⊥平面SAC②平面S
如图在三棱锥S.-ABC中平面SAB⊥平面SBCAB⊥BCAS=AB.过A.作AF⊥SB垂足为F.点
如图所示在三棱锥S.—ABC中SO⊥平面ABC侧面SAB与SAC均为等边三角形∠BAC=90°O.为
如图所示在四边形ABCD中AD∥BCAD=AB∠BCD=45°∠BAD=90°将△ABD沿BD折起使
-BCD,则在三棱锥A.-BCD中,下列命题正确的是( )
A.平面ABD⊥平面ABC
平面ADC⊥平面BDC
平面ABC⊥平面BDC
平面ADC⊥平面ABC
已知三棱锥S-ABC的所有顶点都在球O.的球面上SC是球O.的直径若平面SCA⊥平面SCBSA=AC
三棱锥S—ABC中∠SBA=∠SCA=90°△ABC是斜边AB=a的等腰直角三角形则以下结论中:①异
1
2
3
4
如图在三棱锥S﹣ABC中平面SAB⊥平面SBCAB⊥BCAS=AB过A作AF⊥SB垂足为F点EG分别
如图在三棱锥S.-ABC中∠SBA=∠SCA=90°△ABC是斜边AB=a的等腰直角三角形给出以下结
已知三棱锥S.ABC的三视图如图所示.在原三棱锥中给出下列命题①BC⊥平面SAC②平面SBC⊥平面
①
②
①③
①②
如图三棱锥P.-ABC中PA⊥平面ABC∠BAC=90°PA=AB则直线PB与平面ABC所成的角是_
如图在三棱锥V-ABC中平面VAB⊥平面ABC△VAB为等边三角形AC⊥BC且AC=BC=OM分别为
如图在三棱锥SABC中平面SAB⊥平面SBCAB⊥BCAS=AB过点A.作AF⊥SB垂足为F.点E.
如图在三棱锥S.ABC中平面SAB⊥平面SBCAB⊥BCAS=AB.过A.作AF⊥SB垂足为F.点
如图在三棱锥S.-ABC中平面SAB⊥平面SBCAB⊥BCAS=AB.过A.作AF⊥SB垂足为F.点
表面积为40π的球面上有四点SABC且△SAB是等边三角形球心O到平面SAB的距离为若平面SAB⊥
在三棱锥S—ABC中∠SAB=∠SAC=∠ACB=90°且AC=BC=5SB=.如图所示1证明平面S
如图在三棱锥S—ABC中侧面SAB与侧面SAC均为等边三角形∠BAC=90°O为BC中点. 1证明
如图所示四边形ABCD中AD∥BCAD=AB∠BCD=45°∠BAD=90°.将△ADB沿BD折起使
BCD,则在三棱锥A.
BCD中,下列结论正确的是( )
A.平面ABD⊥平面ABC B.平面ADC⊥平面BDC
平面ABC⊥平面BDC
平面ADC⊥平面ABC
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OnceImetataxidriverinhislate10s.He1anddrovemetomydestination.OnthewayIaskedhimhowhis2was.Hetoldmebrieflythatitwasjustfinebutthecostofgaswas3hurtinghisbottomline.Wethenenteredintoaspiriteddiscussionaboutthe4environment. Hetoldmethathehad5whilehuntingforanothertypeofworkbecauseofhisbackground.Iama6criminalhesaidstraightforwardly.PeoplelookatmyrecordandthenI'mtoast完蛋了he7.IknowI8butI'veturnedmylifearoundandhavebeen9forseveralyearshewentontoexplain. Itisnever10tostartanewlifeIsaidbutthemostimportantthingisthatyouarestartingandthatyouhave11. Thedriverseemed12ashelookedback.Likewhat?heasked.Youcangobackto13evenpart﹣timeifyoudon'twanttodriveataxifortherestofyourlifesoyoucan14foratradeyouareinterestedin.Ireplied. Ifeltamomentofpainforhimbecauseheisstillinatypeof15eachday.Ihavemetmanyotherpeoplelikehimovertheyears﹣theonly16isthattheyhavenevercommittedcrimes.Thesearepeoplewhoalreadyhavegoodjobsandgoodreputationsbutaretotally17withtheirlives.Thedailyprisontheygotoisonewhereworkis18whereeachdayisfullofworrywishingforsomethingbetter.Thisisaprisonofthe19. Ifthisisyourdailylifeknowthatthereisalwaysanopportunityto20yourlife.Thedecisionisyoursandyoursalone. 1A.tookmeaway B.pickedmeup C.droppedmeoff D.sentmeback 2A.health B.family C.business D.study 3A.possibly B.really C.hardly D.merely 4A.job B.office C.finance D.security 5A.motivation B.experience C.confidence D.difficulty 6A.dangerous B.professional C.former D.escaped 7A.warned B.criticized C.threatened D.complained 8A.messedup B.brokeup C.hurriedup D.wokeup 9A.hopeful B.clean C.tough D.quiet 10A.worthwhile B.useful C.possible D.easy 11A.strengths B.experiences C.choices D.friends 12A.worried B.surprised C.relieved D.satisfied 13A.school B.jail C.normal D.court 14A.care B.ask C.qualify D.account 15A.fantasy B.job C.prison D.game 16A.advantage B.limitation C.requirement D.difference 17A.dissatisfied B.patient C.unfamiliar D.delighted 18A.appreciated B.hated C.expected D.envied 19A.fortune B.fame C.hope D.mind 20A.change B.accept C.protect D.devote
Ihadbeenlivinginawhirl:studyingtheorganattheUniversityofArizonaconductingaspeechclinicintownandteachingaclassinmusicalappreciationattheDesertWillowRanchwhereIwasstaying.Iwasgoingtopartiesdanceshorsebackridesunderthestars.OnemorningIcollapsed.Myheart!Youwillhavetolieinbedforayearofcompleterestthedoctorsaid.Hedidn'tencouragemetobelieveIwouldeverbestrongagain. Inbedforayear!Tobeinvalid﹣﹣﹣perhapstodie!Iwasterror﹣stricken!Whydidallthishavetohappentome?WhathadIdonetodeserveit?Iswept.Iwasbitter.ButIdidgotobedasthedoctoradvised.AneighborofmineMr.Rudolfanartistsaidtome:Youthinknowthatspendingayearinbedwillbeatragedy.Butitwon'tbe.Youwillhavetimetothinkandgetacquaintedwithyourself.Youwillmakemorespiritualgrowthinthesenextfewmonthsthanyouhavemadeduringallyourpreviouslife. Ibecamecalmerandtriedtodevelopanewsenseofvalues.Ireadbooksofinspiration.OnedayIheardaradiocommentatorsay:Youcanexpressonlywhatisinyourownconsciousness.Ihadheardthewordslikethesemanytimesbeforebutnowtheyreacheddowninsidemeandtookroot.IdeterminedtothinkonlythethoughtsIwantedtoliveby:thoughtsofjoyhappinesshealth.IforcedmyselfeachmorningassoonasIawoketogooverallthethingsIhadtobegratefulfor.Nopain.Alovelyyoungdaughter.Myeyesight.Myhearing.Lovelymusicontheradio.Timetoread.Goodfood.Goodfriends.Iwassocheerfulandhadsomanyvisitorsthatthedoctorputupasignsayingthatonlyonevisitoratatimewouldbeallowedinmycabin﹣﹣﹣andonlyatcertainhours. NineyearshavepassedsincethenandInowleadafullactivelife.IamdeeplygratefulnowforthatyearIspentinbed.ItwasthemostvaluableandthehappiestyearIspentinArizona.ThehabitIformedthenofcountingmyblessingseachmorningstillremainswithme.Itisoneofmymostpreciouspossessions. 1Thewriterhadtolieinbedforayearbecause. A.shewasterror﹣strickenatthattime B.shehadaseriousheart﹣attack C.shewaswornoutbecauseofhardwork D.thedoctorwantedhertodoso 2Whentoldtolieinbedtotakeayear'srestthewriter. A.wasverygratefultothedoctor B.becameveryworried C.turnedtoaneighborMr.Rudolfforhelp D.thoughtofherbitterexperiencesinthepast 3ThereasonwhythewritersaidIamdeeplygratefulnowforthatyearIspentinbedliesinthat. A.sheledaverycomfortablelifethatyear B.shebecameusedtolyinginbed C.sheperfectlyrecoveredfromherillness D.shecametoknowhowtoleadanactivelife 4Thewritertoldusofherstorymainlyto. A.tellusthatweshouldbegratefulforwhatwehavehad B.introduceherselftousbecauseshewaswiseandkind C.explainthatlyinginbedforalongtimeisnotaterriblething D.encourageustoachieveasmuchaswecan
The13thofJune1325IleftTangiermybirthplacewiththeintentionofmakingthepilgrimagetoMecca去麦加朝圣…toleaveallmyfriendstoabandonmyhomeasbirdsabandontheirnests.SobeginsanoldmanuscriptinalibraryinParis﹣thetraveldiaryofIbnBattuta. AlmosttwocenturiesbeforeColumbusthisyoungMoroccansetoffforMeccareturninghomethreedecadeslaterasoneofhistory'sgreattravelers.DrivenbycuriosityhejourneyedtoremotecornersoftheIslamicworldtravelingthrough44moderncountriesthreetimesasfarasMarcoPolo.LittlecelebratedintheWesthisnameiswellknownamongArabs.InhishometownofTangierasquareahotelacafeaferryboatandevenahamburgerarenamedafterhim. IbnBattutastayedinMeccaasastudentforseveralyearsbuttheurgetotravelsoontookover.InoneadventurehetraveledtoIndiaseekingprofitableemploymentwiththesultan﹣theMuslimrulerofDelhi.Onthewayhedescribedhisgroupbeingattackedintheopencountryby80menonfootandtwohorsemen:…IwashitbyanarrowandmyhorsebyanotherbutGodinhisgracepreservedme…InDelhithesultangavehimthepositionofjudgebasedonhispreviousstudyatMecca.ButthesultanhadanunpredictablecharacterandIbnBattutalookedforanopportunitytoleave.WhenthesultanofferedtofinanceatriptoChinaheagreed.IbnBattutasetoffinthreeshipsbutmisfortunestruckwhilehewasstillontheshore.Asuddenstormgroundedandbrokeuptwoshipsscattering散播treasureanddrowningmanypeopleandhorses.Ashewatchedthethirdshipwithallhisbelongingsandslaves﹣onecarryinghischild﹣wascarriedouttoseaandneverheardfromagain. AfteralifetimeofamazingadventuresIbnBattutawasfinallyorderedbytheSultanofMoroccotoreturnhometosharehiswisdomwiththeworld.Fortunatelyheagreedandwroteabookthathasbeentranslatedintonumerouslanguagesallowingpeopleeverywheretoreadabouthisunparalleledjourneys. 1WhatcanwelearnaboutIbnBattutafromthepassage? A.HehadgreatinterestintheIslamicworld. B.Hereturnedtohishomelandtowriteabook. C.HisjourneyswerelessimportantthanMarcoPolo's. D.Hisjourneyswereverycommonforpeopleofthattime. 2TheSultanofDelhigaveIbnBattutaapositionofjudgebecause. A.IbnBattutahadstudiedinMecca B.IbnBattutahadbeenajudgebefore C.IbnBattutahadbeenpopularwithArabs D.IbnBattutahadtraveledtomanycountries 3Whichisthebesttitleforthepassage? A.TheLearnedIbnBattuta B.AVisitortoMecca C.TheTravelsofIbnBattuta D.DesireforAdventures
Whenbuildinghousespeopleusedtothinkaboutnotonlytheclimateoftheareasbutalsothebuildingmaterialsandthefashionsfortheirhouses.Howeversinceelectricitybecamemoreandmoreexpensivepeoplebegantopaymuchmoreattentiontotheenergytheycouldgetfortheirhousesandthenewwaystheycouldfindtoprotecttheirhousesfrombothcoldandheat. Nowhousesofanoldyetnewtypehavebeenwidelybuilt.Insomepartsoftheworldpeoplesharetheirhouseswiththeirlivestock家畜.Duringcoldweathertheygathertheircowsgoatsorotheranimalsandkeepthemonthefirstflooroftheirhouses.Thereasonsarethattheanimalscanbeprotectedfromthecoldandthattheycanhelptoheatthehousesaswell.Thebodyheatgivenoffbytheanimalsrisestothesecondfloorofthehouseswherepeoplelive.Bysharingtheirhouseswiththeirlivestockpeoplegainasourceofheat. Peoplewholiveinornearcitiesdonotusuallykeeplivestock.Howeverhomebuildersusethefactthatheatrises.Thisnaturallawcanbeusedinbuildinghousesintheseareas.Insteadofkeepinglivestockonthefirstfloorbuildersfillitwithlargerocks.Astheyareopentothesun'sraysduringcoldweathertheserockstakeinheat.Theyalsogiveofftheheatandofcoursethewarmairrisesintothelivingareasofthehouses.Sothesehousesareenergy﹣saving. House﹣buildingbecomesagreatchallenge挑战tobuildingdesignersandenergyengineers.Theytrytomeetthischallengebylearningfromoldtraditionsandbyusingmoderntechnology.Andsomedayinthefuturepeoplewillbeabletoliveinmoreenergy﹣savinghouses. 1Whatdidpeoplebegintoconsideraselectricitywasnolongercheap? A.Theclimateoftheirareas. B.Theenergyfortheirhouses. C.Thefashionsfortheirhouses. D.Thebuildingmaterialsfortheirhouses. 2Peopleinsomeareasgainasourceofheatby. A.keepingtheirlivestockdownstairs B.protectingtheirlivestockfromthecold C.sharingtheirhousesonlywiththeircows D.livingonthesecondfloorwiththeirlivestock 3Theunderlinedwordsnaturallawinthethirdparagraphrefertothefactthat. A.heatraisesthetemperatureinthehouses B.heatgoesintheupwarddirection C.heatgoesupiftemperatureisraised D.heatincreasesthetemperatureofrocks
假定你是李华你的同班同学__的家乡遭受台风彩虹TyphoonMujigae袭击洪水毁坏了家园你作为班长代表班级给正在抗洪的他写一封慰问信要点如下: 1.对该同学表示关心; 2.向其提供一些帮助如捐助和补习; 3.表达希望和对其重建家园的信心; 注意: 1.词数80左右. 2.可以适当增加细节以使行文连贯. 3.开头已给不计入词数. DearWangGang We'resosorrytohearthatasevereTyphoonMujigaehityourhometownleavingyourhouseinruins. Yourssincerely LiHua
MospeoplenowadaysownadevicethatfeaturesartificialinwiththeliesofSiralwaystheretogreetuswithafriendlyvoice.ButtheMicrosoft'sXiaolceisdifferent.Launchedin2014fortheChinesemarketshehasacreativeedgeoverhercompetitors. WhilemostAIassistantssimplyreadoutinformationtheygetonlinesuchasmovielistingsorweatherforecastsXiaolcehasrealnessthattheothersck.IndeedifyouaskednicelyshecouldreadyouapoemfromhernewweeklycolumninWestChinaCityDaily.ThenewspaperhasbeenprintingXiaolce'sself﹣pennedpoetryeachweeksinceAug19takenfromherownbookofpoemsTheSunlightthatLosttheClassWindow. ToturnXiaoiceintoamasterofpoetryMicrosoftscientistsfedhertheworksofover500influentialmodernpoetsincludingthoseofHuShiinHuiyinXuZhimoandWenYiduoreportedChinaDaily.Thisledtoherfiguringoutawritingstyleofherownandcreatingover70000originalpoemswith137usedtoproducethebook. MostofthepoemsareindistinguishablefromthosewrittenbyhumansandXiaolce'sbookevengotgoodfeedbackfromexperts.Xiaolce'sworkcarriesastrangetaste.ThemoreyouchewonitthemoreinterestingitbecomesZhangZonggangaliteratureprofessorattheNanjingUniversityofScienceandTechnologytoldtheSouthChinaMorningPostButitseemsnoteveryoneisafan. Thepoemsdisgustedmewiththeirslipperyandrhythm.ThesentenceswereaimlessandsuperficiallackingtheinnerlogicforemotionalexpressionYuan﹣basedpoetYuJiantoldChinaYouthDaily. Thisisn'tthefirstAIistoattemptpoetry.LastyearGoogle'sParseyMcParsefacemadesomepoemsofitsownalthoughtheywerebrandedmiserableandmournfulbyreviewers. WhileitseemslikeAlisbecomingmoreintelligentandlessartificialallthetimewhenitcomestocreativityperhapsthisisonejobthatsoftwareshouldleavetoushumans. 1WhathasmadetheMicrosoft'sXinolcedifferentfrommostAlassistants? A.Artificialintelligence B.Emotionalexpression. C.Toneandrhythm D.Creativityandrealness 2WhichofthefollowingaboutXiaolceisTrueaccordingtothepassage? A.Xiaolceimitatesinfluentialmodempoetstowritepoems B.Allherpoemsareexactlylikethosewrittenbyhumans C.EveryonedoesnotenjoyXinolce'swork. D.XiaolceisthefirstAltowritepoems. 3WhatisthewritersattitudetowardsthecreativityofAI? A.Hopeful. B.Doubtful C.Concerned. D.Ambiguous.
下列关于传统发酵技术应用的叙述正确的是
某种H+﹣ATPase是一种位于膜上的载体蛋白具有ATP水解酶活性能够利用水解ATP释放的能量逆浓度梯度跨膜转运H+.①将某植物气孔的保卫细胞悬浮在一定pH的溶液中假设细胞内的pH高于细胞外置于暗中一段时间后溶液的pH不变.②再将含有保卫细胞的该溶液分成两组一组照射蓝光后溶液的pH明显降低另一组先在溶液中加入H+﹣ATPase的抑制剂抑制ATP水解再用蓝光照射溶液的pH不变.根据上述实验结果下列推测不合理的是
Attitudeisn'tquiteeverythingwhenitcomestobeingsuccessfulbutattitudeplaysapartineverystageofyourlife.Apoorattitudegetsmorepeople1thananyothersinglefactorandagoodattitudegetspeoplejobsandhelpsthem2thosejobsmorethananyotherfactor. Yourattitude3manypeoplefromyourfamilytothestrangeronthestreetcorner.Yourattitudeisparticularlyimportantwhenyou4seeminglyhopelesssituations.Losingajoborafriendbecauseofapoorattitudeis5. Youcanfindatleasttwo6tolookateverything.Apessimistlooksfordifficultyintheopportunitywhileanoptimistlooksforopportunityinthedifficulty.Apoetoflongagoputthe7betweenoptimismandpessimismthisway:Twomen8outfromprisonbars﹣﹣﹣onesawmud;theothersawstars. Unfortunatelymanypeoplelookonlyatthe9andnotattheopportunitythatlieswithintheproblem.Many10complainaboutthedifficultyoftheirjobsforexamplenotrealizingthatifthejobwere11theemployerwouldhiresomeonewithlessabilityatalowerwage.Asmallcoincanhideeventhesunifyouholdthecoincloseenoughtoyour12.Sowhenyougettooclosetoyourproblemsto13objectivelyaboutthemtryto14howyourvisioncanbe15.Takeastepbackandlookatthesituationfromanewangle. Youcan'tdoanythingtochangethefactthataproblem16butyoucandoagreatdealtofindtheopportunitywithinthatproblem.You're17abettertomorrowbydoingyourbesttodayand18aplanofactionforthetomorrowsthatlieahead.19justrememberto20apositivementalattitude. 1A.hired B.fired C.employed D.engaged 2A.offer B.supply C.keep D.create 3A.affects B.costs C.makes D.trains 4A.lose B.predict C.judge D.face 5A.unfortunate B.unnecessary C.inconvenient D.impossible 6A.desires B.ways C.spirits D.solutions 7A.importance B.necessity C.similarity D.difference 8A.looked B.glared C.celebrated D.concluded 9A.everything B.situation C.problem D.possibility 10A.employers B.employees C.bosses D.secretaries 11A.simple B.tough C.difficult D.interesting 12A.ear B.nose C.eye D.mouth 13A.worry B.ignore C.admit D.think 14A.keepinmind B.keepintouch C.getridof D.doawaywith 15A.observed B.blocked C.imagined D.doubted 16A.appears B.works C.exists D.contains 17A.guaranteed B.persuaded C.satisfied D.convinced 18A.struggling B.developing C.dreaming D.balancing 19A.Inthisrespect B.Incontrast C.Inotherwords D.Inaword 20A.consider B.amuse C.occupy D.maintain
回答下列与生态系统相关的问题. 1在森林生态系统中生产者的能量来自于生产者的能量可以直接流向答出2点即可. 2通常对于一个水生生态系统来说可根据水体中含氧量的变化计算出生态系统中浮游植物的总初级生产量生产者所制造的有机物总量.若要测定某一水生生态系统中浮游植物的总初级生产量可在该水生生态系统中的某一水深处取水样将水样分成三等份一份直接测定O2含量A另两份分别装入不透光甲和透光乙的两个玻璃瓶中密闭后放回取样处若干小时后测定甲瓶中的O2含量B和乙瓶中的O2含量C.据此回答下列问题. 在甲乙瓶中生产者呼吸作用相同且瓶中只有生产者的条件下本实验中C与A的差值表示这段时间内C与B的差值表示这段时间内A与B的差值表示这段时间内.
在真核细胞的内质网和细胞核中能够合成的物质分别是
IgrewupinanagewhenIhadtowaitforalmosteverything.Classicmovieswereshownontelevision.Andofcourseonehadtobehomeattheappointedtimetowatchthem.TheWizardofOzforexamplewasbroadcastonlyonceayear.Thesteadilyheighteningsenseofexpectationasthebroadcastdateapproachedwasalmosttoomuchformy10﹣year﹣oldhearttobear. Andthentherewasmoney.Thebanksdidbusinessonweekdaysonly.Theyopenedat9andclosedat4.Youneededmoneybutdidn'tmakeittothebankontime?Wellcheckunderthesofacushionsorborrowfromfamilyorfriends. Suchwastheworldasrecentlyasthe1970s.Everythingseemedtooperateonastrictclockandthewordsondemandhadnomeaning.Thiswasthewaythingsworkedanditwasallweknew. Andthenseeminglyovernighteverythingchanged.ItsuddenlyseemedasifIneverhadtobeanywhereatanappointedtimebecauseeverythingwasavailableallthetime.Thechangedtimesontheotherhandhaveencouragednothinglessthanaconstantsenseofurgencywhichisironic讽刺性:Ifwecanhaveanythingwewantanytimewewantitshouldn'twebelesshurried?Theansweristhatanondemandlifestylehascreatedanappetiteforspeed:IfIcanhavesomethingthisfastwhycan'tIhaveitfaster?RecentlyIreadabookthathasFSTRgetit?writtenacrossitscover.Oneofitsmetaphors隐喻wastelling:Firsttherewasthefresh﹣squeezedlemon;thentherewasthelemonademix;nowwejustbuythelemonadebythegallon加仑. AndsoonthishotdayIwenttothesupermarketandboughtthreefreshlemons.Isqueezedthemintoatallglass.ThenIfilledtheglasswithcoldwatericeandateaspoonofsugar.FreshlemonadeinhandIwentoutsidesatinmylawnchairandlookedoutovertheriver. Yestimepassesquickly.Butnowandthenitdoesn'thaveto. 1HowdidtheyoungauthorfeelaboutwatchingTheWizardofOz? A.Excited B.Surprised C.Touched. D.Worried 2What'stheauthor'sattitudetowardtheconceptconveyedinbookhereadrecently? A.Positive. B.Optimistic. C.Cautious. D.Opposing. 3Whatdoestheauthortrytoconveybymakinglemonadehimself? A.Hisprideinmakingthemosttastyjuice.. B.Hissatisfactionofmakinguseofmoderntechnology. C.Hisdisapprovalofthedemandsofahurriedage. D.Hisdisappointmentatthelemonadeinthesupermarket. 4Whatcanbeasuitabletitleforthetext? A.Howdowebalancespeedandwork? B.Wewaitedanditwasworthit. C.Whydoestimepassquicklynow? D.Weworrybutitmakesnosense.
赫尔希和蔡斯的T2噬菌体侵染大肠杆菌实验证实了DNA是遗传物质下列关于该实验的叙述正确的是
假设你是李华.你校英文报正在征集关于如何保持身体健康的短文.请根据以下提示用英语写一篇短文. 1.健康的饮食; 2.适当的运动; 3.良好的生活习惯. 注意: 1.词数80左右. 2.可适当增加细节以使行文连贯.
某种植物的羽裂叶和全缘叶是一对相对性状.某同学用全缘叶植株植株甲进行了下列四个实验. ①让植株甲进行自花传粉子代出现性状分离 ②用植株甲给另一全缘叶植株授粉子代均为全缘叶 ③用植株甲给羽裂叶植株授粉子代中全缘叶与羽裂叶的比例为11 ④用植株甲给另一全缘叶植株授粉子代中全缘叶与羽裂叶的比例为31 其中能够判定植株甲为杂合子的实验是
我国生物多样性较低的西部沙漠地区生长着一种叶退化的药用植物锁阳该植物依附在另一种植物小果白刺的根部生长从其根部获取营养物质.下列相关叙述正确的是
下列关于加酶洗涤剂的叙述错误的是
如图为初级精母细胞减数分裂时的一对同源染色体示意图图中1~8表示基因.不考虑突变的情况下下列叙述正确的是
下列关于产纤维素酶菌分离及运用的叙述不合理的是
物质W是一种含氮有机物会污染土壤.W在培养基中达到一定量时培养基表现为不透明.某研究小组欲从土壤中筛选出能降解W的细菌目标菌.回答下列问题. 1要从土壤中分离目标菌所用选择培养基中的氮源应该是. 2在从土壤中分离目标菌的过程中发现培养基上甲乙两种细菌都能生长并形成菌落如图所示.如果要得到目标菌应该选择菌落进一步纯化.选择的依据是. 3土壤中的某些微生物可以利用空气中的氮气作为氮源若要设计实验进一步确定甲乙菌能否利用空气中的氮气作为氮源请简要写出实验思路预期结果和结论即. 4该小组将人工合成的一段DNA转入大肠杆菌使大肠杆菌产生能降解W的酶酶E.为了比较酶E与天然酶降解W能力的差异该小组拟进行如下实验请完善相关内容. ①在含有一定浓度W的固体培养基上A处滴加含有酶E的缓冲液B处滴加含有相同浓度天然酶的缓冲液C处滴加三处滴加量相同. ②一段时间后测量透明圈的直径.若C处没有出现透明圈说明若AB处形成的透明圈直径大小相近说明.
假定你是李华.因你班地理老师MrLee出差在外明天上午的地理课改为英国文学课请按以下要点口头告知大家: 1.课程变动情况; 2.说明原因; 3.课前预习任务布置. 注意: 1.词数80左右; 2.可适当增加细节以使行文连贯.
下列关于观察植物细胞有丝分裂实验的叙述正确的是
下列关于细胞内蛋白质和核酸的叙述正确的是
假定你住在一个涉外小区社区委员会请你帮忙用英文以短文的形式写一封电子邮件将周末农家果摘活动的安排传达给住户. 要点: 时间:下周六上午8.00至1100 内容:采摘苹果 报名:下周四下午500前:社区办公室 提示:带帽子手套等 注意: 1.词数:80左右 2可适当增加细节以使行文连贯 参考词汇:社区Community
如图为燕麦胚芽鞘经过单侧光照射后甲乙两侧的生长情况对照组未经单侧光处理.下列叙述正确的是
如图为某次光合作用色素纸层析的实验结果样品分别为新鲜菠菜叶和一种蓝藻经液氮冷冻研磨后的乙醇提取液.下列叙述正确的是
Thisyeartheheadmasteroftheschoolrecommendedabooktous.ThebookisTheElement:HowFindingYourPassionChangesEverythingbyRobinson.TheElement元素1thepointatwhichthethingsweare2aboutandthethingswearegoodatcometogether.Theauthorsaysitis3tofindourElementnotjustforourown4butfortheimprovementofourworld. MickFleetwoodisoneofthemostfamousrockdrummersintheworld.5thetestsshowedhisintelligencewaslowwhenhewasinschool.Hismindwouldgo6whenhisteacheraskedhimtorecitethealphabetbackwards.7Mick'slearningdisabilitydoesn't8hiswaytosuccess.Hecomesfromahomewherehisparentscouldseewhatis9hislimitsandunderstandthepoor10performancehardlydooms注定onetofailure. Mick'slowscoredidn't11hisparents.Theyknew12himfromschoolandtheteststhat13onlyanarrowrangeofintelligencemaybethepathtoasuccessfulcareer.Insteadof14Mickasalosertheyunderstandthathehasagreattalentforsomethingthatascoreonatestcannever15. Inschoolthereisanefforttohelpstudents16whattalentstheyhave.ButthisisonlyonepieceofthePuzzle17isstressedbyRobinson.Theotherpieceisfinding18aperson'stalentandtheloveof19thattalentintersect交又. IhaveenjoyedthisbookandIreally20theguidanceofthisbook. 1A.refersto B.attachesto C.belongsto D.turnsto 2A.particular B.anxious C.certain D.enthusiastic 3A.reasonable B.natural C.vital D.convenient 4A.agreements B.arrangements C.qualification D.accomplishment 5A.instead B.However C.Moreover D.Therefore 6A.blank B.wrong C.bad D.mad 7A.Honestly B.Actually C.Fortunately D.Obviously 8A.cutdown B.cutaway C.cutthrough D.cutoff 9A.beneath B.within C.across D.beyond 10A.physical B.mental C.academic D.daily 11A.amuse B.annoy C.affect D.alarm 12A.defending B.withdrawing C.prohibiting D.discouraging 13A.describe B.evaluate C.adjust D.convey 14A.selecting B.appointing C.classifying D.recommending 15A.indicate B.distribute C.acquire D.circulate 16A.pickout B.figureout C.carryout D.pointout 17A.where B.that C.which D.as 18A.how B.where C.why D.what 19A.preparing B.correcting C.exercising D.accelerating 20A.acknowledge B.benefit C.admit D.strike
Withtheirpipesandlidstoavoidspillscoffeecupshavelongbeenthesubstituteforadults.NowStarbucksisgoingallinontheconceptbyswearingtogetridofstrawsby2020﹣﹣andit'sallforaverygoodreason.Thismoveisananswertoourownpartnersaboutwhatwecandotoreducetheneedforstraws.Notusingastrawisthebestthingwecandofortheenvironment.InplaceofplasticstrawsStarbucksplanstoofferrecyclablelidsforalliceddrinksandperstrawsforcoffee.ThetransitionisalreadytakingplaceinStarbucks'hometownofSeattlewhereabanonplasticstrawswentintoplaceonJulyI.Byrollinghistnl2800ofherorsby2020ecompsaystheyareannuallyremovingmorethanonebillionstrawsfromgoingintocirculation﹣andpotentiallytheocean.Starbucks'decisiontograduallystopusingsingle﹣useplasticstrawsisashiningexampleoftheimportantrolethatcompaniescanplayinstoppingthetideofoceanplastic.Witheightmillionmetrictonsofplasticenteringtheoceaneveryyearwecannotaffordtoletindustrysitonthesidelines.Marinelifehasa50%deathratewhenitswallowsplasticyetresearchersbelievetherewillbemoreplasticintheoceanthanfishbytheyear2050ifthisrateoflittercontinues.Thatmeanstherecanbeanimmediatepositiveimpactifweswapplasticstrawsforenvironmentallyfriendlyalternatives.ThesmartdesignonthecupforcolddrinkscomesfromStarbucks'in﹣houseteamofdesignersandhasbeenindevelopmentfortwoyears.Howevertheannouncementcomesasoutcry倒彩increasesoverthedangersthatplasticstrawscancausetomarinelife.Othercompaniesmakingtheeco﹣friendlyswapalsoannouncedplanslastmonthtotestalternativestoplasticstraws.1WhydoesStarbucksdecidetogetridofplasticstraws?A.Todecreaseitscost.B.Tosatisfythecustomers'needs.C.Tocreateagreenerplanet.D.Toenlargeitsbusinessworldwide.2Theunderlinedword'transition'inparagraph2refersto.A.courseB.changeC.circulation.D.conflict.3What'sthetextmainlyabout?A.Starbucksisthrowingawayplasticstrawsforaworthycause.B.AsalespromotionofanewbrandbyStarbucksisbeingdoneC.Scientistsaremakingeffortstosolveoceanplasticpollution.D.Environmentallyfriendlymaterialwillreplaceplasticstraws
OnedaywhenIwasaboutnineyearsoldIranintomymother'sbedroomandopenedthedresser.Theninthetopdrawerwasasmall1jewelrybox.Iwasfascinatedbyitstreasures.ThenIsawtherewassomething2underapieceofcloth.3theclothIfoundalittlewhitechipofchina.Whydidmymotherkeepsucha4thing?Shiningslightlyinthelightit5noanswers. SomemonthslaterIwassettingthedinnertablewhenmyneighborMargeknockedatthedoor.Cominginand6thetableMargesaidOhyouareexpectingcompany.I'll7anothertime. NocomeoninMumreplied.Wearenot8anyone. Butisn'tthatyourgoodchina?Margeasked.I'd9trustkidstohandlemygooddishes! Mumlaughed.Tonight'smyfamily'sfavoritemeal.Ifyousetyourbesttableforan10mealwithguestswhynotforyourown11?Afewbrokenplatesareasmall12topayforthejoyweget.Thensheadded13everychipandcrackhasastorytotell. Mumwenttothecupboardandtookdownaplate.ShesaidSeeingthis14ontheedgehere?IthappenedwhenIwas17. Hervoice15.Onedaymybrotherinvitedayoungmantodinnerandsathimnexttome.Iwasso16thatwhenItooktheplateit17andknockedagainstthefork.Astheyoungmanwasleavinghe18apieceofbrokenchinainmyhandwithoutsayingaword. Icouldn'tforgetaboutthatplatewiththe19chip.Iwentuptotakeoutthelittlewoodenjewelryboxagain.Iexaminedthechip20.Thechipwhichmymotherhadsavedwithcarebelongedtotheplateshebrokeonthedayshemetmyfather. 1A.silver B.gold C.china D.wooden 2A.hidden B.unpaid C.removed D.fixed 3A.Covering B.Tearing C.Seeking D.Lifting 4A.broken B.genuine C.beautiful D.valuable 5A.found B.invented C.offered D.selected 6A.glaringat B.glancingat C.lookingon D.spyingon 7A.goby B.passby C.stopby D.standby 8A.inviting B.expecting C.consulting D.celebrating 9A.always B.sometimes C.never D.regularly 10A.common B.strange C.unbelievable D.special 11A.family B.relative C.neighbor D.ancestor 12A.value B.fault C.bet D.price 13A.However B.Though C.Besides D.Otherwise 14A.break B.scene C.spot D.design 15A.hardened B.softened C.sharpened D.weakened 16A.nervous B.anxious C.surprised D.pleased 17A.jumped B.escaped C.slipped D.left 18A.threw B.laid C.examined D.picked 19A.replaced B.penniless C.remaining D.missing 20A.secretly B.carefully C.gratefully D.proudly
某研究小组切取某种植物胚芽鞘的顶端分成甲乙两组按下图所示的方法用琼脂块收集生长素再将含有生长素的琼脂块置于去顶胚芽鞘切段的一侧一段时间后测量胚芽鞘切段的弯曲程度α角测得数据如下表据此回答问题. 1生长素在胚芽鞘中的运输属于极性运输这种运输的方向是. 2上图中α角形成的原因是. 3据表可知乙组中左右两侧的琼脂块所引起的α角基本相同但小于甲琼脂块所引起的α角原因是.
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