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设函数f(x)=|x﹣3|﹣|x+1|,x∈R. (1)解不等式f(x)<﹣1; (2)设函数g(x)=|x+a|﹣4,且g(x)≤f(x)在x∈[﹣2,2]上恒成立,求实数a的取值范围.
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高二下学期数学《》真题及答案
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设函数fx=2sin若对任意x∈R.都有fx1≤fx≤fx2成立则|x1-x2|的最小值为_____
设fx为定义在R.上的奇函数若当x>0时fx=log31+x则f-2=
-1
-3
1
3
设函数fx=x3-ax-bx∈R其中ab∈R Ⅰ求fx的单调区间 Ⅱ若fx存在极值点x0且fx1=
设函数fx是定义在R.上的偶函数且对任意的x∈R.恒有fx+1=fx-1已知当x∈[01]时fx=1
设fx为定义在R.上的奇函数当x≥0时fx=3x﹣2x+aa∈R.则f﹣2=
﹣1
﹣4
1
4
.设fx是定义在R.上的奇函数当x≤0时fx=2x2-x则f1等于
-3
-1
1
3
设fx是定义在R.上的奇函数当x≤0时fx=2x2-x则f1=
-3
-1
1
3
设函数fx=log44x+1+axa∈R.1若函数fx是定义在R.上的偶函数求a的值2若不等式fx+
设函数fx是定义在R.上且周期为3的函数当x∈[01]时fx=x+1则f2014=
1
2
3
2014
设fx是定义在R.上的奇函数当x≤0时fx=2x2-x则f1等于
-3
-1
1
3
设函数fx是定义在R.上的偶函数且对任意的x∈R.恒有fx+1=fx﹣1已知当x∈[01]时fx=1
设a为常数a∈R函数fx=x2+|x﹣a|+1x∈R.1若函数fx是偶函数求实数a的值2求函数fx的
已知函数fx=x-a2x-bab∈Ra
设函数fx是定义在R.上的偶函数且对任意的x∈R.恒有fx+1=fx-1已知当x∈[01]时fx=1
设函数fx=x-13-ax-bx∈R其中ab∈R I求fx的单调区间 II若fx存在极点x0且fx
设fx是定义在R.上的奇函数当x≤0fx=2x2-x则f1等于
-3
-1
1
3
设函数fx=xn+bx+cn∈N+bc∈R.1设n≥2b=1c=-1证明:fx在区间1内存在唯一零点
给出以下命题:①函数fx=|log2x2|既无最大值也无最小值;②函数fx=|x2-2x-3|的图象
设a>0且a≠1则函数fx=ax在R.上是减函数是函数gx=2-ax3在R.上是增函数的______
设函数fx=x2-4x+3gx=3x-2集合M.={x∈R.|fgx>0}N.={x∈R.|gx
(1,+∞)
(0,1)
(-1,1)
(-∞,1)
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Iteachatauniversityandrecentlyhadaninterestinginteractionwithastudentwhoapproachedmydeskwithanassignment.Iwatchedashe1itfromhispocketandheldthecrumpled皱皮sheetouttome. What'sthat?Iasked.His2:Mywork. Iwasshocked.AllIcoulddowasstareatitlongenoughto3myvoice.ThenItoldhimtoredothe4andhanditbacktomeasaclean5andspotlesscopy.Asthestudent6Ipickedupthemerestanger. IfIhavesome7asateacherthenthisisit:quality.Inthelong8ofmyteachingcareerIhavegivenmystudentsgreatcreativefreedomand9manyextensionsofdeadlines.Butmy10ofqualityremainsanchoredinconcrete.IhavealwaysfeltthatshouldI11onthisoneessentialissuethenallislost. Sowhatbecameofmy12withthecrumpledpaper?Hegavemethepaperlikeasoldierpresentingsomethingtoaking13acatwhichiswhyI14him.Icalledhimback.WesatdowntogetherandI15hisdraftwhichwasdisorganized.Iexplained16.andclearlythatone'sfirsteffortisexactlythat:astart.Andwetookitfromtheremovingaparagraphdeletingthe17wordorsentenceand18grammar. Oncethosebasicthingswere19mystudentaskedArewedone?NotyetIsmiled.Onelaststep.Itoldhimtoreadhisworkoutloudandlistentohiswords.Afterhe20heloweredthepaperandlookedatmewithhisexpressionfilledwithhope. 1A.ruined B.pulled C.blocked D.harvested 2A.belief B.solution C.notice D.response 3A.repair B.recover C.raise D.recognize 4Aarrangement B.preparation C.adaptation D.assignment 5A.explicit B.flat C.long D.sharp 6A.twisted B.registered C.withdrew D.deposited 7A.complaint B.celebration C.appreciation D.attraction 8A.lesson B.distance C.course D.silence 9A.excused B.prohibited C.required D.allowed 10A.expectation B.assumption C.comprehension D.judgement 11A.burstout Bcutdown C.givein D.keepup 12A.career B.teacher C.draft D.student 13A.ratherthan B.orrather C.otherthan D.aswellas 14A.forgave B.scolded C.troubled D.influenced 15A.torn B.introduced C.examined D.selected 16Ahopefully B.specially C.strangely D.quietly 17A.difficult B.unnecessary C.valuable D.unconditional 18A.copying B.stressing C.correcting D.reviewing 19A.handled B.listed C.enjoyed D.tested 20A.demanded B.finished C.recorded D.settled
Ourteacherstriedteachingusaboutdeathduringnursingtraining.AsastudentnurseIknewIwouldseedeathinmy1.Ihadnoideaofthe2itwouldhaveonme3. ThefirstpersonIsawdiewasanelderlymanJohnwhohadbeen4forweeks.Hisheartwas5andthehealth﹣careteamwaskeepinghimcomfortableand6hissymptoms.Hehadstoppedspeakingdaysbeforebutwasstillawakeattimesandhis7whenwespoketohimwasbeautiful. WhenIcameontothe8onemorningthenightstaffsaidhehaddeteriorated恶化overnightandhad9lefttoleave.AtrainednurseandIgavehimabedbathshavedhimandchangedhissheets.ForthenextsixhoursI10hishandandtalkedtohim.Thedoctorcameinregularlyandaskedifheneededmorepainreliefbutheseemed11mostofthetime.Heonly12openedhiseyestosmileatme.Earlyintheafternoonthenursecamebackinandwewashedhisfaceand13hishair.Asshewasjustabouttoleavetheroomshestrokedhishairandsaid:OhJohnjust14.Minuteslaterhedid. Ithasbeen20yearssinceJohn'sdeath.Ihaveseen15deathsinmytimenursing.Ihaveseenstaffgofarbeyondthe16oftheirjobsto17thatapatienthasasgoodadeathaspossible.Iremembersomeoftheotherfacesbutnoneisquiteas18asJohn's.Heandtheprofessionalswhowere19himtaughtmethatit20howwetreatthosewhoaredying. 1A.life B.career C.mind D.family 2A.impact B.difference C.reflection D.affection 3A.instead B.regardless C.therefore D.however 4A.insisting B.challenging C.struggling D.recovering 5A.striking B.failing C.beating D.aging 6A.comforting B.decreasing C.disappearing D.relieving 7A.face B.eyes C.smile D.expression 8A.ward B.classroom C.hospital D.department 9A.days B.hours C.minutes D.seconds 10A.held B.reached C.hugged D.touched 11A.silent B.painful C.peaceful D.anxious 12A.frequently B.occasionally C.hardly D.easily 13A.combed B.tied C.washed D.smelt 14A.comeon B.passaway C.letgo D.goaway 15A.priceless B.constant C.considerate D.countless 16A.qualifications B.ability C.expectations D.exception 17A.pretend B.assume C.believe D.ensure 18A.beautiful B.vivid C.pale D.scary 19A.caringfor B.lookingfor C.bringingup D.cheeringup 20A.trains B.works C.influences D.matters
已知单位向量满足•=0.若点C在∠AOB内且∠AOC=60°mn∈R则下列式子定成立的是
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IfyouliveinWashingtonD.C.orRedwoodCalif.youmayhaveglimpsedasmallboxyrobotrollingalongalocalsidewalkmindingit'sownbusinessbutattractingtheattentionofmanyacuriousonlooker.TheautonomousmachineswerepartofapilotprogramlastyearbyStarshipTechnologiesfocusedondeliveringmealsfromlocalrestaurantsindozensofcitiesaroundtheworld. TodaymorethaneverpeopleleadabusyanddiverselifeLexBayerStarship'sCEOsaidinastatementonline.Thehassleofneedingtorearrangeyourlifeforadeliverywillbecomeathingofthepast.Youdon'thavetoswitchyourworkingfromhomedayreschedulemeetingsvisitalockerdrivetoapostofficeorcontactadeliverymanallbecauseofamisseddelivery. Thepackagedeliveryserviceisnotavailabletoeveryonejustyet.Thecompanysaidit'srollingouttheserviceinMiltonKeynesEngland.Thewheeledrobotshaveatopspeedof4mphandcandetectobstaclesfromasfaras30feetaway.TherobotcanoperatethroughjustaboutanythingNickHandrickheadofoperationsforStarship'sD.C.officetoldTheWashingtonPost'sMauraJudkislastyear.Ifyouhadsomethingintheway﹣astick﹣it'sabletoclimbtheedgesofaroad. BygivingcustomerscontrolofwhendeliveriesoccurStarshipTechnologiesisofferingitsserviceasawaytobattlepackagetheft.InitsannouncementthecompanycitedstatisticsfromaWakefieldResearchPollforComcastlastyearthatfoundthat3in10Americanswholiveinhousesortownhouseshavehadpackagesstolen. Tosignupfortheservicewhichcostsalittlemorethan$10permonthcustomersneedtodownloadthecompany'sapp.CustomersthencreateaStarshipDeliveryAddressauniqueaddressinsideaStarshipfacilityinsteadofaresidencewheretheycanhavepackagessentfromplacessuchasAmazon.comOnceapackageisdeliveredtotheStarshipaddresscustomersreceiveatextthatallowsthemtoscheduleahomedeliveryviarobot. 1Whichcanbestreplacetheunderlinedwordhassleinparagraph2? A.failure B.expectation C.safety D.trouble 2Whatproblemisthedeliveryrobotfacing? A.Thereisalimittoitsservicearea. B.Ittakeslongertodeliverpackages. C.Itcoversashortdistanceeachtime. D.Itcan'tsensethebarriers20feetaway. 3Howdoesthepackagebyarobotavoidbeingstolen? A.Thecompanyshortensthedeliveryhour. B.Thepackageisdeliveredtothehousedirectly. C.Itsdeliverytimeisinthecontrolofcustomers. D.Thecustomersareinformedofitsdeliverytimeinadvance. 4WhatcanbeinferredaboutStarshipDeliveryAddressinthelastparagraph? A.Itisarealhomeaddressofthecustomers. B.Itcanarrangedeliveryrobotsforthecustomers. C.Itisacheapersolutiontothedeliveryofpackages. D.Itsendsthepackagesmainlytosomeshoppingplatforms.
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ItiswithmixedemotionsthatIwenttotheyoungcriminalcentereveryfewmonthstogivevaccinations接种疫苗.OntheonehandIfeelluckytobeabletoprovideaservicethatmayhaveapositivehealtheffectontheresidents.ButontheotherhandIfeelasenseofsadnessanddisappointmentasIseetheprisonersbeingescorted押送byguardstothenursingunit. Mylastvisitwasverymemorable.Forsomereasontherewasalightnessintheair.MorethaneverbeforeIfeltalightnessasIspokewitheachperson.Wesharedstoriesandsmilesandfears.Eventhetoughestprisonersseemedtobesurroundedbylight.AsamotherIsawthemasnotonlyyouthbeingpunishedforcrimesbutalsoaschildrenwhohavethepotentialtochangeforthebetter.Mostofthemwantedtotalklonger!Theywerereachingouttous!Itfeltright. Therewasonemoreprisoner.Hewaslimitedtoadifferentunitinalonelycell.Wewereaskedifwewereokaygoingdownthere.Wesaidthatwewere.Twoguardsescortedusdownandwhenweenteredtheareainstanttearswelledupinmyeyes.Theareawassad.Theseguardsdidn'tsmile.Weenteredthecellandhadtomakedowithwhatwasthere. WeweredonebutIdidn'twanttoleave.Igavethe17yearoldagentletouchandsmileasIexplainedwhattodoregardingthesideeffects.AtfirsttherewasnoresponsesoIjustlookeddownathisbarefeetandthentomysupplies.IthoughtthatIhadbetterpackup.SuddenlyhelookedupatmeandsmiledbeforehesaidThanksandthenhegavemeathumbs﹣up.IsmiledbackandsaidYou'rewelcome.Takecareofyourself. Itwaswonderfultoreceiveakindresponsefromsomeonewhowasinsuchaharshplace.Aswewalkedbacktothemainentrancewedidn'tspeak.Wheretherecanbeasmilethereishope.Sometimessmilescanbeverypowerful. 1Whatcanweknowabouttheyoungintheyoungcriminalcenter? A.Theyreceivedregularmedicalservice. B.Theyweretreatedunfairly. C.Theystayedinbadconditions. D.Theywereforcedtotaketreatment. 2Whatwasspecialaboutthecenterthelasttimetheauthorwentthere? A.Shewasaskedtosharestories. B.Everyprisonerwaskindtoher. C.Theyoungpeopletalkedfreely. D.Shesensedarelaxingatmosphere. 3Whatdidtheyoungmanthinkoftheauthor? A.Hedislikedherforhersympathy. B.Hereallyappreciatedherkindness. C.Hethoughtshewouldchangehislife. D.Hethoughtshewasjustanordinarydoctor. 4Whatimpressedtheauthormostinthisstory? A.Theyoungman'ssmile. B.Themedicalcareforprisoners. C.Thepunishmenttotheprisoners. D.Thedifferencebetweentheyoungmanandothers.
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TheInterContinentalShanghaiWonderlandwhichwasbuiltintothesideofa1formalabandonedquarry采石场about20milessouthwestofShanghaihasbeenconsideredtheworld'sfirstundergroundhote1ortheworld's2lowskyscraper. Thetopfloorofthehotelislocatedatgroundlevelwitharoofcoveredingreenerywhile16floorsofthehotelarelocatedbelowground.Underwaterareanothertwofloors3guestscanobserveschoolsoffishthrougha15﹣metre﹣wideglasswindow.Apartfromthoseunderwater4roomeveryroominthehotelfeaturesabalconywithviewsofaglass﹣enclosedartificialwaterfall5rundownthequarrywalls.Thehotelisalsotakingadvantage6itslocationinsideasteep288﹣feetdeepquarryandisprovidingbungee﹣jumpingandrock﹣climbingattractionstothrill﹣seekingvisitors. Thehoteltook10yearstocompletewithtotalcostover﹩151million.Over5000peopleparticipatedinthe7constructofthehotel.ThechiefengineerontheprojectChenXiaxiangsaidhisteamregistered39patentsand8makehundredsoftechnologicalbreakthroughs.It'sbeenafightagainstgravityhesaid. Thehotel9designwitheco﹣friendlyprinciplesproducesitsownpowerheatingandlightingthrough10useofgeothermal地热的andsolarenergy.Roomsstartfrom4000Chineseyuanaround﹩576onsomeonlinehookingsites.
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Haveyoueverwantedtoknowwhatadecoratorwasthinkingwhilechoosingmaterials?1Herearetipsyoushouldknowbeforeyoubuyplantsatthenursery. Anyplantsyoupickwillbeeasiertogrowiftheylikethespaceyou'replantingthemin.Sofirstgetagoodsenseoflight.Isthespotsunnyalldayorisitonlysunnyintheafternoon?Ifthespotdoesn'tseemuchdirectsunlookforshade﹣lovingplants.2Italsoinvitesattackfromdiseaseandpests. 3Afteraheavyraindoesitdryoutafteracoupleofdaysorstaywetforawhile?Plantsthatlikethesoilonthedrysidearerottenwhentheirrootsstaywet.Plantsthatdon'tlikeitdrywillfadeawayiftheydon'tgettodrinkenough.Knowingaboutthesoilhelpsyougrowhealthyplants. Howmuchspacedoyouhave?4Whatlooksliketheperfectplantmightheaburdenifitgrowstoobig.Youhavetoprune修剪itbackeverymonthjusttousethesidewalkorseeoutofwindows. Thelastthingyoushouldknowistoconsideryourownsparetime.Someplantsneedmorecarethanotherswhileothersneedless.5Varietieslikepurpleconeflowerforexampleneeddeadheadingtokeepproducingnewflowersandtopreventalotofyoungplants.Theygrowfinewithoutanycareinashortperiod. A.Howmuchyouwanttowater? B.Afteryouknowwhatthelightislikefocusonthesoil. C.Placingsun﹣loversbeneathatreekeepsthemfromflowering. D.Doyouwonderhowtoshoptherightplantsforyourcourtyard? E.Puttingmatureplantsinasunnyspotresultsinlargerandgreenerleaves. F.Payattentiontotheplants'maturesizeandknowwhatspaceyouhavetofill. G.Thereforeheawarehowmuchtimeyou'rewantingtospendtakingcareofthem.
Whilestaringoutofthewindowduringaflightnoteveryonewillthinkcarefullyaboutthequestionwhyairplaneshaveroundedwindowsratherthansquareones. Overtheyearsaerospaceengineeringhasmadehugestepsinairplanetechnologymeaningplanescancarrymorepassengersandgofaster.Theplaneshavealsochangedshapetoincreasesafety﹣includingthewindows.Ascommercialairtraveltookoffinthemid﹣20thcenturyairlinecompaniesbegantoflyathigheraltitudestolowertheircost﹣theairdensity密度isloweruptherecreatinglessdrag阻力forairplanes.Howeverhigheraltitudescamewithproblemslikethefacthumanbeingscan'treallysurviveat30000feet.Tomakethatpossiblethecabinwaschangedtoacylindrical圆柱体shapetosupportthepressureinside.Butatfirstplanebuildersleftinthestandardsquarewindowsandthisexpansionmeantdisaster.ThedeHavillandCometcameintofashioninthe1950s.Withaclosedcabinitwasabletogohigherandfasterthanotheraircraft. Howeverwherethere'sacornerthere'saweakspot.Windowshavingfourcornershavefourpotentialweakspotsmakingthemlikelytocrashunderstress﹣suchasairpressure.Bycurvingthewindowthestressthatwouldeventuallybreakthewindowcornerisdistributedandthechanceofitbreakingisreduced.Roundedshapesarealsostrongerandresistdeformation变形andcanthussurvivetheextremedifferencesinpressurebetweentheinsideandoutsideoftheaircraft. Fortunatelydesignersfiguredoutthelackofdesignprettyquick.Nowwehaveniceroundedairplanewindowsthatcanresistthepressureoftravelingaltitude.Itgivesbeingabletogazeoutofyourwindowtotheworldfrom35000feetawholenewoutlookdoesn'tit? 1Whydidairlinesaimtoflyathigheraltitudes? A.Toincreasesafetyoftheplane. B.Tohelptheplanetotakeoff. C.Tosavemoneyforlessdrag. D.Tocarrymorepassengersandgofaster. 2WhatdoestheunderlinedwordsdeHavillandCometinParagraph2referto? A.Aplanet. B.Aband. C.Anaircraft. D.Adesign. 3Whichistheadvantageoftheroundedwindow? A.Itreducesthepossibilityofbreakingup. B.Itweakensthestrengthofairpressure. C.Itincreasestheairpressure. D.Ithelpstosurvivetheextremeweather. 4Wheredoesthistextcomefrom? A.Anewspaperonsafedriving. B.Amagazineonfashiondesign. C.Awebsiteonsurvivalskills. D.Asciencebookonflying.
已知三个事件ABC两两互斥且PA=0.3P=0.6PC=0.2则PA∪B∪C=.
Haveyoueverspentanafternooninthebackyardmaybegrillingorenjoyingabasketballgamewhensuddenlyyounoticethateverythinggoesquiet?Thereisanoldphrasecalmbeforethestormoftenusedinasituation﹣aquietperiodjustbeforeagreatactivityorexcitement.Accordingtoourownexperienceweknowthereisactuallycalmbeforethestorm.Butwhatcausesthiscalm?Andisitalwayscalmbeforethestorm?Let'shearwhatscientistshavetosay. Aperiodofcalmhappensinaparticularkindofstormthesimplestkindofstorm﹣asingle﹣cellthunderstorm.Inthistypeofthunderstormthereisusuallyonlyonemainupdraftwhichiswarmdampairanddrawnfromplacesneartheground.Stormsneedwarmanddampairasfuelsotheytypicallydrawthatairinfromsurroundingenvironment.Stormscandrawintheairthatfittheirneedfromalldirections﹣evenfromthedirectioninwhichthestormistraveling. Asthewarmdampairispulledintoastormsystemitleavesalow﹣pressurevacuum真空comingafter.Therisingairmeetsthecolddryairthathasalreadyexistedinthestormcloudsthusthetemperatureofthewarmdampairdropsandthewatervapour水蒸汽initchangesintotinydropsthatareapreconditionofrain.Thesedropsaccumulateandbuildonlargerparticleslikedustuntiltheygrowlargeenoughtoformraindrops. Thiswarmdampairkeepsmovingupwardsbutitbecomescooleranddrierduringitstripthroughcloud.Whenitreachesthetopofthecloudtheairgetsspitout被挤出atthetop.Thisairissentrollingoutoverthebigthunderclouds.Fromtheretheairgoesdown.Warmanddryairisrelativelystableandonceitcoversaregionthatairinturncausesthecalmbeforeastorm. Mostthunderstormsthoughdon'tstartwithcalm.That'sbecausemostareactuallygroupsofstormswithcomplexwindpatterns.There'ssomuchairmovingupanddownstormgroupsthatthecalmbeforethestormneverhappens.Insteadbeforethestormitmightbereallywindy! 1Whichbestfitsthedescriptionofaparticularkindofstorm? A.Astormwithairdrawnfromeverydirection. B.Athunderstormwithoutstrongwinds. C.Athunderstormwithasingleshape. D.Astormfueledbymovingairfromtheground. 2WhatdoestheunderlinedworditinParagraph3referto? A.Coldanddryair. B.Warmanddampair. C.Coldanddampair. D.Warmanddryair. 3Whichdoesthewritermostlikelyagreeto? A.Presenceofthecalmreliesonstableair. B.Stormhappenswithoutairmovingupanddown. C.Thedriertheairisthebiggerthestormwillbe. D.Notallthunderstormsstartwiththecalm. 4Whatisthepassagemainlyabout? A.Causesandeffectsofaheavystorm. B.Anexplanationofthecalmbeforeastorm. C.Apersonalexperienceofaheavystorm. D.Abriefdescriptionofapeacefulstorm.
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加:在缺词处加一个漏字符号Ʌ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:在错的词下划一横线并在该词下面写出修改后的词. 注意:1.每处错误及其修改均仅限一词; 2.只允许修改10处多者从第11处起不计分. My71﹣year﹣oldgrandparunasmallfoodstandinanightmarketinmycityprovidelocalsnacksforpeopleworkingovertime.Receivingpaymentshasalwaysbeenaproblemforhimbeforemyhelp.Heoftenhadtofeelinhispocketforchangesoncoldnightswhilekeepingeyeonfoodintheoven.AfterlearningthisIhelpedhimsetupwithmobilepaymentappslikeWeChatPayandAlipay.MygrandpaiscontentwithwhichIdidforhimforabout95percentofhiscustomersnowpaywithhisphones.Mobilepaymenthasbecomeanessentialpartofoureverydaylife.Itnotonlydeepchangesthelifeofyoungpeoplebutalsoprovidesconvenientfortheelderly.
设ABC是平面内共线的三个不同的点点O是ABC所在直线外任意﹣点且满足若点C在线段AB的延长线上则
下列关于平面向量的说法中不正确的是
IntheUKwethrowawayabout2.5billiondisposable一次性的coffeecupseveryyear.Thebedthingisthelayerofpolyethylenethatdoesn'tletthecupleakandthelidwhichismostoftenmadeofpolystyrene.Thismakesthemabitofabarrier.Asaresultmostofthecupsendupinlandfillthoughtheyarerecyclableintheory. Butthereareeffortsunderwaytosettlethisproblem.OnecompanyBiomeBioplasticshascomeupwithafullyrecyclablecupthatusesnaturalmaterialssuchaspotatopowder.Mr.Minesitsgeneralmanagerbelievesthatthisisthefirsttimethatbioplastichasbeenusedfordisposablecupsandlidsthathavetodealwithhotliquid.Andthey'restillfullyrecyclable.AnothersolutionhasbeenputforwardbyFrugalpac.Theyhavepatentedacupwithalightly﹣attached一lacticinn.一layer.ThiscanbeeasilyseparatedduringtherecyclingandoffersamorepracticalsolutionthanchangingourcurrentrecyclinghabitssaysFrugal﹣pac'sfounderMartinMyerscough. SafiaQureshisaysIndiahasprovidedtheinspirationforhersolution.SheputsforwardthatweusereturnableandreusablecupswhicharetrackedandcollectedbyhercompanyCupClub.Theywillberesponsibleforcollectingwashingandredistributingthecleancupstoparticipatingtradesmen.OnefinalcreativeapproachcomesfromCupffee.Theyhavecombinedgrainstoformacupwhichcanbeconsumedoncethedrinkisfinished.Itcanholdacoffeeforupto40minutesandwillbiodegrade生物降解withinweeks. Whetheranyoftheseideasisaperfectfitforthisdisposableproblemonlytimewilltell.Allitmayrequireisalittlemorethinkingoutsidethebox. 1WhatdoweknowaboutthedisposablecoffeecupsintheUK? A.Fewarerecycled. B.Theyarestronglydesigned. C.Theyhavequalityproblems. D.Mostareenvironmentallyfriendly. 2WhatcanweinferaboutFrugalpac'scus? A.Theyareeasytopatent. B.Theyarepartlyrecyclable. C.Theyenjoygreatpopularity. D.Theysuittraditionalrecyclinghabits. 3InwhatwayareCupffee'scupsdifferentfromothers? A.Theyaretime﹣consumingtoproduce. B.Theycanbreakdowninstantly. C.Theyaretoeveryone'staste. D.Theycanbeeatable. 4Whatcanbeasuitabletitleforthetext? A.BadHabitsofUsingCoffeeCups B.ProblemwithCurrentCoffeeCups C.CreativeWaystoRecycleCoffeeCups D.ReasonsforProducingNew﹣styleCoffeeCups
要得到函数y=sin2x的图象只需将函数y=sin2x﹣的图象
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