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在斜△ABC中,设角A,B,C的对边分别为a,b,c,已知asin A+bsinB﹣csin C=4bsinBcosC,CD是角C的角平分线,且CD=b,则cosC=( )
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高三下学期数学《》真题及答案
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环境中的内分泌干扰物是与某种性激素分子结构类似的物质对小鼠的内分泌功能会产生不良影响.回答下列问题. 1通常机体内性激素在血液中的浓度与靶细胞受体结合并起作用后会. 2与初级精母细胞相比精细胞的染色体数目减半原因是在减数分裂过程中. 3小鼠睾丸分泌的激素通过体液发挥调节作用.与神经调节相比体液调节的特点有答出4点即可.
当人体失水过多时不会发生的生理变化是
15分Asisknowntoallapositiveparent﹣childrelationshipis1benefittothephysicalandmental2growofchildrenbutkeepingahealthyparent﹣childbond3needtheeffortsofbothparties. Parentsshouldtaketheresponsibility4improvetheirrelationshipwiththechildren.Whatmattersisspendingqualitytimewiththeirchildren5tighttheirscheduleis.Forinstancetheycaneat6mealtogethergotosportingeventstogetherorwatchtheirchildren'sfavoriteTVshowstogether7cancontributegreatlytomakingtheirchildrenfeelsafeand8love. Childrenontheotherhandshouldlettheirparentsknowtheyappreciatewhattheirparents9doforthem.Ifpossibletheycangivetheirparentsagiftonaspecialdayorhelpwithhousework10aregularbasis. Isfohealthyparent﹣childrelationshipiswithoutconflict.Butaslongasparentsandchildrenmake jointefforttheycansettletheconflictandenjoytheirtimetogether.
30分OnceImetataxidriverinhislate30s.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
15分KewGardensliesonthebanksoftheRiverThamesinsouthwestLondonwhich1coveralargearea. Thereisavisitorcenternearthegate2youcanpickupaguidebookforthegarden.NeartheentrancearethePalmHouseandsomehugebananatreesaswellasotherplantsfromthehotandwetpartsofAfricaandAsia.ClosetothePalmHouseisamuseumshowingmanyphotosofpeoplethroughouthistorywhohaveusedplants3makedifferentthingsfrompapertoboats. YournextstopmightbethePagodawhichlookslikea4traditionChinesetemplebuilding.Thereisabamboogarden5manyChinesebambooplantsandChinesepalmsinit.TheRoseGardenisbeautifulinsummerandtheWoodlandisanareafullofhugeredwoodtreesfromCalifornia. AvisittoKewGardensisnotcompletewithout6visitKewPalace.At7itbackisawonderfulgardenwhichcansatisfyvisitors'curiosityaboutcommonplantsthatcanbeusedasmedicines. VisitingKewGardensis8enjoyableandeducationalexperienceforpeopleofall9age.Itdoesn'tmatterwhetheryouhaveeverbeentoKewGardensornot.VisitKewGardensonce10youwillfallinlovewithit.
10分Thisisthebiggesteducationprovideryou'veneverheardof.Untilnow.TheAlisonproject﹣AdvancedLearningInteractiveSystemsOnline﹣hasalreadysignedupmorethantwomillionstudentstomorethan500onlinecourses.It'saddinganother200000eachmonthandfounderMikeFeerickisconfidentthisexpansioncouldgrowevenmorerapidlyandreachabillionstudentstowardstheendofthedecade.Sohowhasitstayedbelowtheradar?Whilethenewwaveofonlinecourses﹣so﹣calledMoocssuchasCourseraandedXhavebecomedarlingsofthedigitalmediawhyhasAlisonnothadthesameattention?Mr.Feericksaysthebigdifferenceiswhotheyaretryingtoreach.It'stheacademicversusvocational职业的dividebeingplayedoutinthedigitalmarket.'Thepeoplewe'rehelpingdonothaveahugevoice'saysMr.Feerick.WhiletheMoocsareassociatedwithhigh﹣statusuniversitiesAlison'sfocusisonthegreatnumbersofpeoplearoundtheworldneedingtoimprovetheirvocationalskillsandtraining.TherearecoursesinsubjectssuchascomputerskillslearningEnglishbasicaccountancybuildingawebsitefoodsafetyintroductionstolegalstudies.WithinthecomingmonthsIndiaisexpectedtobecomethebiggestsourceoflearnersovertakingtheUKandUS.NigeriaandthePhilippinesarerapidlygrowingmarkets.Mr.Feerickwantstouseonlinetechnologytoofferfreelessonsinthemostimportantbasicskillsthatpeopleneed.Asheputsit99%ofthepeoplearelearningthesame1%ofinformationagainandagain.Hisotherchallengetotheestablishedorderistoquestionthenecessityofexamcertificates.Ifpeoplearestudyingforaspecificskillsuchaslearningtotouchtypeoralanguagehearguesthekeyquestioniswhethertheycanputthelessonsintopractice.1Whatdoestheunderlinedphrase'belowtheradar'inParagraph3probablymean?A.Tryingtocatchup.B.Failingtoattractnotice.C.Failingtomeetdemands.D.Tryingtobecomesuccessful.2TheAlisonprojectisdifferentfromCourseraandedXinthat.A.ithasmoresubjectsB.itoffersfreecoursesC.itdoesn'tmakemoneyD.itfocusesonbasicskills3WhatdowelearnabouttheAlisonproject?A.Itaimstoimprovethelearners'academicscores.B.Itismainlysupportedbyhigh﹣statusuniversities.C.Itwillattractmanylearnersindevelopingcountries.D.MostofitslearnersarefromAsiaatthepresenttime.4WhichwordcanbestdescribeMikeFeerickaccordingtothelastparagraph?A.Practical.B.Creative.C.Diligent.D.Generous.
8分 Somepeoplearesorude! Whosendsane﹣mailoratextmessagethatjustsaysThankyou?Wholeavesavoicemailmessageratherthantextsyou?WhoasksforafacteasilyfoundonGoogle?Don'tthesepeoplerealizethatthey'rewastingyourtime MaybeI'mtherudeonefornotappreciatinglife'slittlepoliteness.Butmanysocialagreedstandardsjustdon'tmakesensetopeopledrowningindigitalcommunication. Intextsyoudon'thavetodeclarewhoyouareorevensayhello.E﹣mailtooisslowerthanatext.Voicemailisanowimpolitewayoftryingtoconnect. MyfatherlearnedthislessonafterleavingmeadozenvoicemailmessagesnoneofwhichIlistenedto.ExasperatedhecalledmysistertoexpresshisdissatisfactionthatIneverreturnedhisphonecalls.Whyareyouleavinghimvoicemail?mysisteraskedJusttexthim. Intheageofthesmartphonethereisnoreasontoaskonce﹣acceptablequestionsabouttheweatherforecastabusiness'sphonenumberordirectionstoahousearestaurantwhichcanbeeasilyfoundonGoogleMaps.Butpeoplestillaskthesethings.Andwhenyouanswertheyrespondwithathank﹣youe﹣mail. Howtohandlethesedifferingstandards?Easy.Consideryouraudience.Somepeopleespeciallyolderonesappreciateathank﹣youmessage.Otherslikemewantnoreply. Theanthropologist人类学家MargaretMeadoncesaidthatintraditionalsocietiestheyounglearnfromtheold.ButinmodernsocietiestheoldcanalsolearnfromtheyoungHere'shopingthatpolitenessnevergoesoutoffashionbutthattime﹣wastingformsofcommunicationdo. 1Theunderlinedwordexasperatedcanbereplacedby. A.worried B.annoyed C.surprised D.tired 2Whydidn'tthewriterreplytohisfather? A.Hedidn'treceiveanyvoicemailmessages B.Heenjoyedcheckinghisvoicemail C.Helikedtextmessagesbetter D.Hedidn'twanttotalkwithhisfather 3Whichofthefollowingdoesthewriteragreeto? A.Peopleneedn'tlearnfromoneanotherintraditionalsocieties B.Peopleneedn'tturntoGoogleforhelpwhenintrouble C.Declaringwhoyouareorsayinghellointextsisnecessary D.Dealingwithvoicemailshouldvarywitheachindividual 4What'sthebesttitleofthispassage? A.Nowadayswhatmeansshouldweuseincommunication? B.Nowadayswhatshouldwedowithtextmessages? C.Nowadaysdoyoulikeleavingothersavoicemessage? D.Nowadaysdoyouneedathank﹣youmessage?
treatsmadebythebelovedHostessbrand.Butaftermorethan80yearsAmericamustbidafondfarewelltothesedesserts.EarlylastweekHostessannounceditwasgoingoutofbusiness.'Manypeoplehaveworkedincrediblylongandhardtokeepthisfromhappening'saidHostessCEOGregoryF.Rayburn.'Hostesshasnootheralternativethantobegintheprocessofwindingdown.'Hostesswasfoundedin1930astheInterstateBakeriesCorporation.AsthecompanygrewitboughtthemanufacturerofWonderBreadoneofthebiggestproducts.WonderBreadwasahouseholdnameinthe1950sand1960s.OvertheyearsthesoftwhiteslicesbecameasAmericanasapplepie.InthepastdecadeshoweverHostesshasexperienceddifficultieswithitsmanagementandhighlaborcosts.Thecompanyhadmoneytroublesinthepastbutthistimetherewasnowaytorecover.Alongwiththelossofsugarytreatscomesthelossof20000jobs.ThedownfallofHostessisduenotjusttothecompany'sfinancialdifficultiesbutalsotoachangingAmerica.Ourcountry'stastesandlifestylesarenotthesameastheywereeightyyearsago.Americanshavebecomemorehealth﹣consciousandtheyaredemandingmorehealthfulfoodproducts.Asamanufacturerofhigh﹣calorieproductsHostessdoesnotfitintothisnewwayoflife.TomakemattersworseforHostessAmericansdonoteatasmuchbreadastheyoncedid.'Moreandmorewe'rechoosingone﹣dishmeals'saidHarryBalzarafoodindustryanalyst.'Thetraditionofbreadasasidedishisfading.'Americansarefindingalternativestotheirmorningtoasttoo.Insteadtheyarechoosingquicksnacksandenergybars.WillTwinkiesbecomeanimageofbygoneAmerica?Hostessfansarehopefulanothercompanywillbuyoutthemakerofthisspongysnackandsecureitsspotonsupermarketshelvesforyearstocome.Wecanonlywait.1Whatdoesthepassagemainlytalkabout?A.Americansdon'tlikebreadnow.B.Hostessisgoingtoclosedown.C.Americaischangingfast.D.Hostessbrandispreparingtosell.2WhichofthefollowingisNOTthereasonthatcausesthedownfallofHostess?A.Financialproblems.B.Hightaxcosts.C.Thechangingtaste.D.Poormanagement.3WhatmaybedirectlyaffectedifHostessgoesoutofbusiness?A.Theculturaltradition.B.Thehealthyproblems.C.Thedevelopmentofeconomy.D.Thesituationofemployment.
25分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. TheysayacathasninelivesandIbelievethatsinceIamnowlivingmythirdlifeandI'mnotevenacat.Myfirstlifebeganin1904whenIwasbornintoafarmingfamily.ThoughstrugglingtomakealivingIstartedmyownfamily.ThiswaswhenIbegantoenjoymyfirstlifehappyinexcellenthealthtwolovelygirlsagoodjobandabeautifulhome.Lifewasapleasantdream.Thenitended.Ibecameaffectedwithadiseaseaffectingfirstmyrightarmandlegandthenmyotherside.Thusbeganmysecondlife… DespitemydiseaseIstilldrovetoandfromworkeachdaywiththeaidofspecialequipmentinmycar.Therewere14stepsinourhomeleadingupfromthegaragetothekitchendoorwhichweremyyardstick标准mychallengetocontinueliving.WhenonedayIwasunabletoliftonefootuponestepandthendragtheotherpainfullyafteritIcouldthenadmitdefeatandliedowntodie.SoIkeptonworkingandclimbingthosesteps.Youmightthinkthatherewalkedamanofcourageandstrength.Notso.Herecrippled跛行abitterlyfrustratedmanwhoheldontoeverything﹣clearmindwifejobandhome﹣becauseofthe14miserablesteps.AsIbecameolderIbecamemorefrustrated. ThenonadarknightinAugustIbeganmythirdlife.FiercewindsandslashingrainbeatdownonthecarasIdroveslowlydownoneoftheless﹣traveledroads.SuddenlyIheardthebangofablowout.Ifoughtthecartostopandsatthereastheseriousnessofthesituationsweptoverme.Itwasimpossibleformetochangethattire.Completelyimpossible.ThenIrememberedthatashortdistanceupalittlesideroadwasahouse.IstartedtheengineanddroveslowlyalonguntilIcametothedirtroadwhereIturnedin﹣thankfully.LightedwindowswelcomedmetothehouseandIpulledintothedrivewayandpressedthehorn. 注意 1.所续写短文的词数应为150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. Paragraph1 Thedooropenedandanoldmancameout. Paragraph2 InthenextfewfrozensecondsIfoundtheoldmanacripplewetthrough!
25分Inthefarawaylandtherewasabeautifulkingdomwithitsuniquerule.Therulesaideveryonemaybecomethekingwithallofhisrightstogovernthecountryforfiveyears.Afterthathemustbecaughthisbodywillbetiedandhewillbethrownawaytoaremoteislandwherethejungleisthickandthereareplentyofwildanimalsandnohuman. Thenonebyonepeoplebecametheking.ThefirstmansaidOkI'mreadytobetheking.Andhebecameakingforfiveyears.Whathedidinhisfiveyearswasenjoyinghisposition.HethrewbigpartieswenttomanybeautifulplacesmarriedmanywomencollectedmanyluxuriousthingsanddidotherthingsthatpleasedhimselfThosewereallhedidandheneverpreparedanythingforhisfuture.Untilonedaythetimecame.OnemorningwhenthekingwokeupsuddenlystrongsoldierscametohispalaceandsaidWecamehereundertheorderofconstitution.Nowit'stimeforyoutobethrownawaytotheremoteisland.Thekingwasn'tsurprisedbuthefeltthattimepassedbytoofast.Hehadenjoyedhimselfinthepastfiveyearsbutnowhehadtoaccepthisdestinywithtearsinhiseyes.Thesoldierssenthimtothedangerousislandandleft.Alltheyheardwasthevoicesofthewildanimalsandthelongscreamoftheformerkingandthensilentagain. Everyotherkingwasthesameuntilayoungmancameanddeclarehiswish.Bytheconstitutionhewasgrantedhiswish.Hewouldbeahugforfiveyearsbeforebeingthrownawaytotheisland.Butifotherkingswouldfollowtheirpassionforhavingfunhedidn't.Thekingwasalwaysseentobethinking. 注意1所续写短文的词数应为150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. Paragraph1 Andnotverylongafterthathemadeasurprisingdecision. Paragraph2 Finallythetimecamewhenthekinghadtobethrownawaytotheisland.
25分AfterstudyforhoursIwentoutsideanduptotheroofnearbyforabreakandwatchedpeopleswimminginthesea.Itwasasunnyday﹣abluecloudlessskyoveracalmsea.ButthenasIlookedinthedistance.Idiscoveredaseriesofthreeorfourbigwavesheadingtowardstheshore.I'dseenthesemini﹣tsunamis小型海啸manytimesbefore.Theywereheadingatspeedinthedirectionoftheswimmingarea.MostpeopleknewtolookoutforthembutfromthescreamsthatstartedcomingfromthebeachIcouldtellsomeonewasintrouble. WithoutthinkingIrandownintothestreetholdingmybodyboard冲浪板onthewayandshoutedatastrangertocallthecoastguard海岸警卫.MyneighborTomhadheardthescreamingaswellandwasalsooutsidewithhisbodyboardsotogetlierwerushedtothestepsthatleddowntothesea. Oncewegotcloserwediscoveredthewaveshadpulledabovandagirlintotheopensea.Iknewthatthenearestboatwouldtakeatleast30minutestoreachus.Iwasn'tusedtothissortofemergency﹣I'dneverbeentrainedasalifeguard﹣butIdidn'tthinktwiceabouttryingtosavethem. IsupposeinawayIwantedtoimpresseveryoneat19adeallikethatcanseemlikeagoodopportunitytoshowoff. TomandIdivedintothewaterandittookus10minutestogettothem.Whenwefinallyreachedthemtheywerealmostlifelesswithonlytheirheadscominginandoutofthewater.Wecouldtelltheywerestillalivefromtheirsmallbreathsbutitwascleartheywouldn'thavebeenabletostaytheremuchlonger.Iheldtheboyandpulledhimovermyboard.Tomthenmovedthegirlontohisboard. Paragraph1 Wediscussedpushingthembacktotheshorebutweweretoofarout. Paragraph2 Thatnightwordcamefromthehospitalthatthetwokidswereingoodcondition.
已知三棱锥P﹣ABC中△ABC为等腰直角三角形AB=AC=1设点E为PA中点点D为AC中点点F为PB上一点且PF=2FB. 1证明BD∥平面CEF 2若PA⊥AC求直线CE与平面PBC所成角的正弦值.
15分Whereveryoulookthesedayssomething'slookingbackatyou.Therearevideocamerasonstreet1cornervehiclesandourownfrontdoors. AChicagocompany2callCoolerScreensbelievesthatyouwon'tmindiftheyputcamerasintothedisplaycases展柜instores.Thecamerasaren'tplacedthere3preventyoufromstealing.Insteadtheyrepartofasystemthattriestoguess4youwillbuynextbasedonhowyoulook. Thedoorsonthecases5bevideoscreensthatshowimagesofthegoodssoacustomercanseewhat'savailableinside.Thescreensalsoshowvividads.Theydecidewhichadstoshowby6studyvideoimagesofthecustomers. Acamerafeedsimagesofeachcustomerintoacomputer7guesseshisorhersexandage.Inadditionthesystemtracks8exactwherethecustomerislooking.Dotheeyescometorest9abottleofRedBullordoestheshopperfancyCocaCola?TheCoolerScreenssysteminstantly10analyzeallofthisdataandthenstartsshowingadsonthecoolerdoor.
8分Beneathasanddune沙丘inBeidaiheliesoneofChina'snewestartgalleriesAsabranchoftheUllensCentreforContemporaryArtinBeijingtheDuneisunlikeanyotheradvancedartmuseuminChina.Mostareremarkablebuildingsstandinginthedowntown.ButtheDuneisquietandprivateitsgalleriesspreadingagainstthesands. HarmonywiththelandscapeandthelocalcommunityisattheheartoftheDune'spurposeItaimstobesustainable可持续的ecologicallyaswellasfinanciallyandtohelpprotecttheenvironmentratherthandestroyingit.Ourworkwasnotjusttodesignaphysicalstructure'saysLiHuadesigneroftheprojectbuttoinventanentirelynewtypeofsystem. Insteadofplacingthemuseumontopofthedunesaswasoriginallyplannedhedecidedtoburythebuildingbeneaththemtoprotectthecoastalecology. Becausethemuseumislitnaturallybyskylightsvisitors'experiencesoftheartworkwillvarywiththeseasonsandtimeofday. TheDune'sinnerpartsaremeanttodevelopacloserelationshipbetweenviewerworkandspace.GoingtoamuseuminChinaoftenfeelslikegoingtoashoppingcentersaysMr.LiIt'sanexperienceofrushedconsumerism消费主义.BycontrasttheDuneremindsviewersofthecaveswherethemostprimitivehumanartwasfirstpainted.ThedesignwasinspiredbyLouisKahnanAmericanarchitectwhoimaginedmuseumsasasocietyofroomswhichencouragepeopletoslowdown.Giventheseparatelocationvisitorswillhavetomakeasincerepilgrimage朝圣totheartasMr.Liputsitratherthanjustahurriedurbanfly﹣by. 1What'sthecharacteroftheDuneinParagraph1? A.It'snoisy B.It'sinthedowntown C.It'sthemostadvancedartmuseum D.It'sburiedbeneathadune 2What'sParagraph2manlyabout? A.theartworksoftheDune B.thepurposeoftheDune C.theside﹣effectsoftheDune D.theoriginoftheDune 3Theauthorwritesthispassage. A.tocomparetheDunewithotherartmuseums B.tocriticizeadvancedartmuseums C.tointroducetheDunetoreaders D.topraiseLiHu'scontributionstotheDune 4Wecanlearnfromthepassagethat. A.theDunewasplannedtobeplacedbeneaththedunesinthebeginning B.viewerscanvisittheDuneanytimeintheday C.visitingamuseuminChinaissincerePigrimagetotheart D.theDunemakesviewersthinkofthecaveswiththemostprimitivehumanart
某种甘蓝的叶色有绿色和紫色.已知叶色受2对独立遗传的基因A/a和B/b控制只含隐性基因的个体表现隐性性状其他基因型的个体均表现显性性状.某小组用绿叶甘蓝和紫叶甘蓝进行了一系列实验. 实验①让绿叶甘蓝甲的植株进行自交子代都是绿叶 实验②让甲植株与紫叶甘蓝乙植株杂交子代个体中绿叶紫叶=13 回答下列问题. 1甘蓝叶色中隐性性状是实验①中甲植株的基因型为. 2实验②中乙植株的基因型为子代中有种基因型. 3用另一紫叶甘蓝丙植株与甲植株杂交若杂交子代中紫叶和绿叶的分离比为11则丙植株所有可能的基因型是若杂交子代均为紫叶则丙植株所有可能的基因型是若杂交子代均为紫叶且让该子代自交自交子代中紫叶与绿叶的分离比为151则丙植株的基因型为.
如果复数a∈Ri为虚数单位的实部与虚部相等则a的值为
10分 Howtobecomeamorethankfulperson Inthebusinessofday﹣to﹣daylifeweoftenforgettostopandbegratefulforthepresentmoment.Beinggratefulisimportantandhasmanymentalandphysicalbenefits.Ifyouwanttoworkonbeingmoregratefultryshiftingyourfocusthroughouttheday.Workonpracticingmindfulnesswhichcanhelpyouappreciatethepresentmoment.1 Begratefulthroughouttheday. Givethankseachmorning.Ifyouwanttoworkonbeingamorethankfulpersonworkonsettingthetoneforgratitudewhenyouwakeup.2Takeamomenttobethankfulfortheabilitytoliveanotherday. Takeafewmomentstolookatthebigpictureaswell.3Howeveryouhavearoofoveryourhead.Yourjobmaynotbepartofyour10﹣yearplanbutyouhavemoneycominginandasenseofpurposeeachday. Expressyourgratitude Expressingyourappreciationcanmakeyourselfandothersmoreawareofit.4Expressinggratitudedoesnothavetobeabigsweepinggesture.Sendsomeoneaquicktextmessagetothankthemforlisteningtoyouandtalkingoveraproblemtheothernight.Leaveanoteinyouroffice'skitchenthankingsomeoneforalwaysrememberingtobringinfreshcoffee. 5 Beslowatappreciatingslighthappinessandtrytoenjoytheaftertaste.Takefivesecondstocloseyoureyesandrememberthesmellofcoffeeasyousitatyourdesk.Smileasyourememberyourco﹣worker'spraise.Don'tjustobservethegood.Workactivelytoembraceit. A.Enjoysmallpleasures. B.Gratitudeisgoodforyou. C.Pausebeforegettingoutofbed. D.Keeptheshortnessoflifeinmind. E.Youmaynothavethebestapartmentintheworld. F.Trytotalkaboutyoursenseofgratitudethroughouttheday. G.Youshouldalsofindabalanceallowingyourselftofeelgrateful.
如果食物链上各营养级均以生物个体的数量来表示并以食物链起点的生物个体数作底层来绘制数量金字塔则只有两个营养级的夏季草原生态系统假设第一营养级是牧草第二营养级是羊和森林生态系统假设第一营养级是乔木第二营养级是昆虫数量金字塔的形状最可能是
30分5pmma'am.What?Mybabycannolongerwaitforthat!Canyoupleaseaskthecrewafavortomakeit1?My3﹣month﹣old﹣babywasalreadyvery2Hisstomachbecamelargerandlargerineachhourthat3. Threedaysagowebroughthimtothe4whereIworkedseveralvomiting呕吐.Iknewthedangerverywellbecausetherewerealready5patientsofthiscasethatwehadencountered.ButitwasnotassimpleasI6Itheldabiggerunknownthreatthatneeded7surgery.Butbeforethedoctorcouldfigureoutthebest8heorderedaCTScanoftheWholeStomach.Itwasscheduledatthemostfamoushospitalofthecity9ourownhospitaldidn'thaveityet. Everythingabouthimsuddenlybecamesounstable.Iknewthathischanceof10becameverythin.SoIwasafraidthathecouldn'twaitforanotherfewhours. Ma'amwe'resoblessed.His11ismovedto3pm. Iwas12butanothermuchbiggerproblem13Ididnothavethemoneyneeded.Ihadtosendmessageswithmy14toborrowmoneytothepersonsinmycontactlist.Ionlyhadfewminutesleftthen.Icriedwhile15amiracletoprovidemewaysrightthen.As16asIgotupfrommykneesmycellphonesuddenlyrang17.Ms.Luceropleaseclaimyourmoneythrough…AndoneafteranotherI18differentmessagestellingmetogetthemoneytheysentformybaby.Ihadthemoneytheninlessthananhour!NotonlyfortheCTScanbutforourimmediateneedsduringourwholehospitalstay! Iwassoawed敬畏的athowdestiny命运19alltheincidentsin.livestocomeupforblessingsthatithaspreparedaheadofus!Butmostofallforthe20signthatHehasshownmethatmybabyshalllive! 1A.later B.longer C.earlier D.shorter 2A.weak B.thin C.strong D.healthy 3A.passedaway B.passedby C.passedon D.passeddown 4A.school B.company C.hospital D.government 5A.meaningless B.valueless C.homeless D.countless 6A.made B.expected C.provided D.felt 7A.fast B.simple C.slow D.immediate 8A.approach B.thing C.tool D.hospital 9A.since B.before C.or D.and 10A.arrival B.survival C.death D.danger 11A.surgery B.result C.recovery D.schedule 12A.nervous B.relieved C.worried D.embarrassed 13A.rose B.raised C.arose D.aroused 14A.request B.command C.suggestion D.order 15A.playingwith B.lookingfor C.prayingfor D.givingup 16A.far B.well C.long D.soon 17A.quietly B.totally C.hardly D.continuously 18A.accepted B.received C.wrote D.sent 19A.found B.built C.arranged D.damaged 20A.first B.second C.third D.fourth
15分假设你是学校的学生会__李华一批来自英国的高中生与你校的高中生开展了为期两周的交流项目.现在他们即将回国你将在欢送会上致辞.请根据以下提示写一篇发言稿. 1.回顾双方的交流项目如学习生活文艺等方面 2.谈谈收获 3.表达祝愿. 注意 1.词数80左右 2.可适当增加细节以使行文连贯.
10分WhenIheardthepianoIwalkedtoMrs.Windsor'shouseandwaitedoutsideasIalwaysdid.ThatmeantshewasworkingwithanotherstudentandIwasnotsupposedtobotherthembyringingthebell.IstoodagainstthewallanddaydreamedwhatI'dratherbedoing.AlmostanythingIsigheddejectedly.IhadbeentutoredenoughtoreadunderstandandevenwritesomemusicalcompositionsbutIjustdidn'thaveagiftforit.Itdidn'tcometomenaturally.IthoughtbacktohappiertimeswhenIwaswritingstoriesandactingthemoutwithmyfriendscuttingupoldclothestomakedressesthatperformerswearinplaysandbuildingsceneryoutofoldthingswefound.ButMrs.WindsorhadofferedtogivemethelessonsforfreesoIfeltmydutytotry. ThedooropenedandWendyBartoncameout.Iwalkedinsatdownonthepianobenchandbegantosortthroughmysheetmusic. HelloIheardavoicebehindmesaysoftlyIturnedaroundtoseealittlegirlstandingbehindmeeatinganapple.ButbeforeIcouldmakeanyresponseMrs.WindsorwalkedintotheroominherusualurgentmannerandannouncedJenniferthisismyniecePasha.PashathisisJennifer.Pashawillbegivingyouyourlessontoday.I'muptomyearsinsomethingelse!shethenexitedtothekitchen. Pashasetherappledownonthesidetableandslidbesidemeonthepianobench. Whatpiecedoyoulikebest?sheasked. Whatdoyoumean?Iasked.They'reallthesametome.Idon'tknow. Youmeanyoudon'thaveafavorite? Nonotreally. Pashalookedatmeratherpuzzledthenopenedmysheetmusictothebeginningpageandaskedmetoplay.Iarrangedmyfingersonthekeysandstudiedthenotesonthepageforamoment.ThenIfrownedandconcentratedtomakethenotesonthepagematchthefingermovementsIhavetoadmitIwasarathermechanicalpianist. AfteraboutapageortwoPashagentlyputherhandontopofmineasiftocalmmyfingers.Therewasalongpause.Whatareyouhearinginthemusic?IlookedatherratherstrangelyandadmittedIdidn'tknowwhatshemeant. Likeastory.Whatstoryisbeingplayingoutwithinthemusic? IguessI'veneverthoughtaboutitbefore.Idon'tknow. HereletmetryandyoulistenPashaadvised. Sheclosedhereyesandtookadeepbreathlettingherfingersdancelightlyoverthekeys.Thenshebegantoplay.Seeitbeginsherebesidesomekindofriver.Hearthewaterflowingbesideyou? Herfingersroseandfellgentlyonthekeys.Nowtheprincessappearsandshe'spickingflowersfromthewater'sedge.AcarefreehappypieceofmusicfilledtheairintimetoPasha'sdancingfingers.Ohbutsheslips!Themusicchanged.Andourprincessisbeingcarriedoffbythefast﹣flowingstream.Quicklytheprincess'shorseseesherplight因境Pashacontinuedandracestotheriver'sedgewhereheswimsouttolethercatchholdofhim.Theymakeittothebankandshehugsherfaithfulhorseandswearsshewillneveragainwearprincessskirtsthatweighherdown.ShewillonlywearjeansandT﹣shirtfromnowon.Pashafinishedwithabigsmileandthenlookedatme. Aren'tyouthegirlwhotellsthestories?sheasked. Iguess.Idotellalotofstories. Ohyes!Allthekidstalkaboutthem.I'veheardaboutyou.Wellallyouhavetodoislearntohearthestoriesinthemusic.That'sallthereistoit. I'veneverthoughtitthatway. Let'stryanotheroneshallwe?Pashasmiledandtogetherweplayedthatafternoonfindingthestoriesinthemusicandlearningthatsometimesittakesafriendtopullyououtoftheriverontodrylandagain. 1Jennifergotlostinthoughtwhenshe. A.playedthepianowithPashaforthefirsttime B.listenedtoPashatellherstoryabouttheprincess C.rememberedhappiertimesofwritingstoriesandactingthemout D.discoveredthatMrs.Windsor'sniecewouldbegivingthepianolesson 2WhichofthefollowingcanbestdescribePasha? A.Creative B.Naughty C.Humorous D.Brave 3Whichofthefollowingisthehesttitleforthetext? A.NeverGiveup B.APianoLesson C.WhyIHatedPlayingthePiano D.AFriendforEver 4Thistextwouldbeprobablyfoundin. A.acollectionofstoriesaboutfriendshipandlearning B.abookofdailyrecordsaboutfamousyoungmusicians C.amagazineseriesaboutthechallengesofovercomingfears D.aseriesofnewspaperarticlesaboutmusicalinstruments
10分 Howtoenjoyschool Schoolisagreatplacewhereyouarealwaysoccupiedinexpandingyourknowledgeandfurtherimprovingyourself.ButSchooldoesn'thavetobeaprison.1Learnsomeconcretestrategiestohelpyouenjoyyourschoollifemakingfriendsandkeepingitfun. Cheeryourselfupeachday.YoucouldwakeupeachmorningwithabadattitudeandeachCorningwillturnintoabadday.Oryoucouldlistentosomeenergetictuneseatabreakfasttoyourtasteandmakeyourschooldaypleasant.2 3Ifitmakesyouhappierandmorecomfortablewithyourenvironmenttrydecoratingyourschoolbagsnotebooklockerandothersuppliesnecessary'forschool.Usestickerscolorfulpens°rotherstufftomakeyourschoolthingsalittlemorefuntocarryaroundwithyou. Joinanafterschoolclub.Ifsagreatwaytomakefriendsbyjoiningaformalcluborgroupatyourschool.4Checkouttheoptionsofferedatyourschoolandconsiderjoiningonethatlinesupwithyourhobbies. Avoiddistractions.5Butitalsorisksgettingyouintotroubleandforcingyoutofallbehindwhenyou'renotpayingattention.Itmaynotseemlikeitbutthebestwaytoenjoythelessonsistolistenmorecloselynotfindwaystodistractyourself. A.Purchasethingstomakeyoufeelhappy. B.Personalizeyourschoolbelongings. C.ItmightseemfunhidinganiPhoneinyoursweatshirtatschool. D.Forinstanceyoucouldjointhemusicloversorchessplayers. E.Ifyoudecidethatyourdaywillbefunitlikelywillbe. F.Joinaclubthatyouhavelittleinterestintomeetsomeoneyoumightnotmeetnormally. G.Whetheryoufindschooldifficultboringorstressfulyoucantrytomakeiteasier.
在直角坐标系xOy中直线l的参数方程为t为参数在以坐标原点为极点x轴正半轴为极轴的极坐标系中曲线C1ρ=2cosθ. Ⅰ求C1与C2交点的直角坐标 Ⅱ若直线l与曲线C1C2分别相交于异于原点的点MN求|MN|的最大值.
如果复数a∈Ri为虚数单位的实部与虚部相等则a的值为
10分TimeaftertimeIamondifferentinternetforumsandIendupcommunicatingwithpeoplewhowanttostartablogorwebsiteandaregoingtogetstartedsoonthinkingaboutitorstillgoingovermyoptionsandsoon.Whileabitofplanningandresearchwillserveyouwellwhenstartinganyprojectoftenmonthslaterthesesamepeoplearestillthinkingaboutit. Whiletherearemanyreasonsthatmaystopsomeonefromevenstartingaprojecttheyhaveinmindfearbeingthemostobvioustheideaofperfectionismseemstobethesecondmost.1 ThereisaproverbTomorrowisoftenthebusiestdayoftheweek.Thereisnosuchthingastheperfectplan.Infactyouspendsomuchtimebeingconcernedaboutgettingeverythingrightandperfectbutitwearsyourinitialenthusiasmdown.2 Yesyoushouldwanttobereachingforexcellencebutwhostartsoutwithbeingexcellent?Excellencewillonlycomefromtrialanderror. Justmakeadecisionandstartfollowingthrough.Forgettryingtobeaperfectionist.3 ItcomesfromthebeliefthatanythingIdothatislessthanperfectisnotworthdoing.Thiswayofthinkingleadstoonebecomingdiscouragedandthenfailedeventostartyourproject. Tostartjustbeginwithsomethingthatisgoodenoughandthenkeepworkingtoimproveonit.Makeabasicplantakeactionandthenstartimprovingtheactualresults.4Letgoofthefearstopthinkingandstartdoingandforgetstartingoutwithit'sgottobeperfect. I'llleaveyouwiththewordsofanactualdoerwhowasnotaperfectpersonandallhisdecisionswerenotperfect.5Youdon'thavetoseethewholestaircasejusttakethefirststep. A.Infactperfectionismisanunhealthybelief. B.I'llprovideyouwithsomeexamplesofaction. C.Yettheonlywaytoasolutionistostartdoing. D.Howeverheisanexampletobefollowedtoday. E.Onceyoubeginit'softenlesspainfultokeepworking. F.Gettingstartedonaprojectisnotalifeanddeathdecision. G.Theresultisthattimepassesandsodoestheperfectmoment.
植物组织培养技术在科学研究和生产实践中得到了广泛的应用.回答下列问题. 1植物微型繁殖是植物繁殖的一种途径.与常规的种子繁殖方法相比这种微型繁殖技术的特点有答出2点即可. 2通过组织培养技术可把植物组织细胞培养成胚状体再通过人工种皮人工薄膜包装得到人工种子如图所示这种人工种子在适宜条件下可萌发生长.人工种皮具备透气性的作用是.人工胚乳能够为胚状体生长提供所需的物质因此应含有植物激素和等几类物质. 3用脱毒苗进行繁殖可以减少作物感染病毒.为了获得脱毒苗可以选取植物的进行组织培养. 4植物组织培养技术可与基因工程技术相结合获得转基因植株.将含有目的基因的细胞培养成一个完整植株的基本程序是用流程图表示.
7.5分AsayoungchildAnnMakosinskiwouldspendhoursexperimentingwithhertoysandothereverydayobjectsaroundhertocreateherowninventions. Nowafirst﹣yearArtsstudentMakosinskiisawell﹣knowninventor.ShewontherecentSustainableEntrepreneurshipAwardofExcellencewhichrecognizescreativebusinesssolutionstosocialproblems一thesamerecognitionwasgiventoBarackObamain2014.Hertwoinventions﹣theHollowFlashlightandthee﹣Drink﹣havebeencausingexcitementinternationallysincetheircreation. WhenMakosinskiwas15yearsoldshecreatedaflashlightpoweredbytheheatofone'shand.Thisinventionwastheresultofa9thgradescienceprojectbuthergoalwastoofferapracticalsolutiontopeoplewithunlimitedaccesstopowerandelectricity.OneofmyfriendsfromthePhilippinestoldmethatshefailedschoolbecauseshehadnolighttostudywithatnightsothatwaskindoftheinspiration.Makosinskiexplained. At12thgradeMakosinskithenwentontocreatethee﹣Drink.Itisacoffeecupthatharveststheextraheatofahotdrinkwhileitcoolsstoresitaselectricityinanintemal内置的batteryandmakesitavailabletochargeanexternaldevicesuchasaphonewhoselifecannowbelongerbyapproximately10to30minutes. Myfavoritepartofcreatinginventionswouldbewhenyouhadtheideaandyouhavetophysicallybuilditanditdoesn'tworkoutshesaid.Soyouhavetofigureoutdifferentwaystosolveit.AlotoftimesI'llgiveupandI'llcomebackafteracoupleofdaysandI'lltakeitupagain. Heradvicetootherstudentinnovators?Startnow.There'snothingholdingyouback.Actuallyyoucandowhateveryouwant.MakosinskisaidIfyouwanttomakesomethingfollowyourheartthengoahead.Ifthere'ssomethingyoureallywanttodoyouwillmaketimeforitandyouwillfindtimeinthedaytodoyourschoolwork. 1Makosinskycreatedthepowerlessflashlightmainlyto A.satisfyherdesiretocreateinventions B.settleproblemsinstudyforherfriend C.helpthosewhoareshortofelectricity D.finishtheassignmentofascienceproject 2Whichofthefollowingismainlyexplainedinparagraph4? A.Howthee﹣Drinkwasinvented. B.Whythee﹣Drinkwascreated. C.Whatthee﹣Drinkbrings. D.Howthee﹣Drinkworks. 3Whichcanbethebesttitleforthispassage? A.PopularInventionsbyaTeenagerGirl B.TeenagerGirlAdvancinginCreation C.ValuableAdvicefromaCreativeGirl D.AwardsGiventoaYoungInventor
随着改革开放的不断深入祖国不断富强人民的生活水平逐步提高为了进一步改善民生2019年1月1日起我国实施了个人所得税的新政策其政策的主要内容包括1个税起征点为5000元2每月应纳税所得额含税=收入﹣个税起征点﹣专项附加扣除3专项附加扣除包括①赡养老人费用②子女教育费用③继续教育费用④大病医疗费用……等.其中前两项的扣除标准为①赡养老人费用每月扣除2000元②子女教育费用每个子女每月扣除1000元. 新个税政策的税率表部分内容如下 级数 一级 二级 三级 四级 … 每月应纳税所得额含税 不超过3000元的部分 超过3000元至12000元的部分 超过12000元至25000元的部分 超过25000元至35000元的部分 … 税率% 3 10 20 25 … 1现有李某月收入29600元膝下有一名子女需要赡养老人除此之外无其它专项附加扣除.请问李某月应缴纳的个税金额为多少 2为研究月薪为20000元的群体的纳税情况现收集了某城市500名的公司白领的相关资料通过整理资料可知有一个孩子的有400人没有孩子的有100人有一个孩子的人中有300人需要赡养老人没有孩子的人中有50人需要赡养老人并且他们均不符合其它专项附加扣除受统计的500人中任何两人均不在一个家庭.若他们的月收入均为20000元依据样本估计总体的思想试估计在新个税政策下这类人群缴纳个税金额X的分布列与期望.
7.5分Believeitornotitistruethatwearelikelytochargeourphoneusingourownbody'senergy.Let'stakealookatthisproduct﹣HandEnergy.HandEnergyisanapple﹣sizeddevicethatchargesourphoneanytimeanywhere. Inatimewherepower﹣banksandsolar﹣powerdeviceshavebecomemainstreamadevicethatletsyouchargedoesn'tsoundveryspecial.Butwhilepower﹣bankshavetobechargedtheold﹣fashionedwayandsolar﹣powerdevicesneedthesuntostoreenergyHandEnergyjustneedsahand.Togetthislittleguytoproduceenergywhichitthenstoresinbuilt﹣inbatteriesallyouhavetodoisholditinyourhandandrotate旋转yourwrists. TouseHandEnergyusersstartbywindingastarterring.Thissendsasignaltoactivatetherotor旋转器atwhichpointtheycanstartrotatingtheirwriststokeeptherotorspinning.ItmightsoundhardtobelievebuttherotorinsideHandEnergyspinsatanaveragespeedof5000rotationsperminutechangingmechanicalpowerintoanelectriccurrentandchargingthebuilt﹣inbatteries.TochargeadeviceallyouhavetodoisconnectittoHandEnergyusingaUSBwire. HandEnergywassuccessfullycrowd﹣fundedonKickstarterraisingover﹩7100000onemonthandwillcomeintothemarketforthemassesinJune2019atapriceof﹩99.Onethingisforsure﹣itbeatspayingthousandsofdollarsonasolar﹣poweredchargingdevice. 1FromthefirsttwoparagraphswecanknowHandEnergyis. A.handytouse B.complexinstructure C.freeofbattery D.solar﹣powered 2HowdoesHandEnergyproduceenergy? A.Byreceivingsignalsfromthestarterring. B.Bykeepingitsrotorspinning. C.Byconnectingittopowersource. D.Byturningelectricpowerintomechanicalpower. 3WhatcanbeinferredaboutHandEnergyfromthelastparagraph? A.Itissortofexpensive. B.Itiswidelyavailable. C.Itispopularwiththepublic. D.Itispromisinginthefuture.
马铃薯块茎储藏不当会出现酸味这种现象与马铃薯块茎细胞的无氧呼吸有关.下列叙述正确的是
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