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（x3+）7的展开式中的x5的系数是 （用数字填写答案）
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高二下学期数学《》真题及答案
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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
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假定你是李华你校将举办主题为中国书法的传统文化讲座.请给你的英国校友Eric写一封电子邮件邀请他参加.内容包括: 1.举办目的; 2.主讲人介绍; 3.听讲前的准备. 注意: 1.词数100左右; 2.可以适当增加细节以使行文连贯; 3.参考词汇:中国书法Chinesecalligraphy.
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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.
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∧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.LastyearZhangPingyupaidvisittoLondon.WorriedaboutthetimeavailableZhangPingyuhadmadealistofthesiteshewantedtosee.ItwastheTowerwhichshevisitedfirst.Fancy!Thissolidstonesquaretowerhadbeenremainedstandingforonethousandyears.Manynewbuildingshadexpandedaroundit.Thereforeitwasstillpartofaroyalpalaceandprisoncombined.TherefollowedStPaul'sCathedralbuiltaftertheterriblefireofLondonin1666.Itlookedsplendidlywhenfirstbuilt.WestminsterAbbeytoowasveryinteresting.ThenjustashecameoutoftheabbeyPingyuheardthefamoussoundoftheclockBigBenringoutthehour.ThenextdayPingyuwasleavingLondontoWindsorCastle.'PerhapsIwillseetheQueen?'shewonderedasshefallasleep.
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.
手机支付也称为移动支MobilePayment是指允许移动用户使用其移动终端通常是手机对所消费的商品或服务进行账务支付的一种服务方式．继卡类支付网络支付后手机支付俨然成为新宠．某金融机构为了了解移动支付在大众中的熟知度对15﹣65岁的人群随机抽样调查调查的问题是“你会使用移动支付吗”其中回答“会”的共有100个人把这100个人按照年龄分成5组然后绘制成如图所示的频率分布表和频率分布直方图． 1求x 2从第134组中用分层抽样的方法抽取6人求第134组抽取的人数 3在2抽取的6人中再随机抽取2人求所抽取的2人来自同一个组的概率．
Thereisnobetterwaytoexperienceaplacethanthroughthelocalcuisine.Withseveralfoodfestivalshappeningacrosstheworldfindplentyofmotivationheretohelpyouyou'reyourbagsandgoonaglobalcookingexploration. MaineLobsterFestivalUS ThefestivalinRocklandMaineisnotedforitsseafood.CelebratedduringthefirstweekendofAugustforfivedaysitoffersfirst﹣classentertainmentfineartcookingcontestsandmore.Itisexpectedthatover20000pounds9072kilogramsoflobsterareconsumedduringthecourseofthefestival. OktoberfestGermany The16﹣daytraditionalbeerfestivalinMunichisthelargestofitskindintheworld.HeldinSeptemberandOctoberthe2013editionsawI.84milliongallonsofbeerserved.AwidevarietyoftraditionalGermandishesincludingroastporksausageandpotatoorbreaddumplingsarealsoavailable.In2019the186theditionwillbeginfromSept.21andlastuntiltact.6.Entryisfree. MentonLemonFestivalFrance Takingplacesince1896thisfestivalisheldinFebruaryandMarchinMentonontheFrenchRiviera.Basedonanewthemeeachyearimpressivesculpturesandfloatsaredeco﹣ratedwith140tonnesoflemonfruits.In2019thefestivalwillheheldfromFeb.16toMarch3onthethemeFantasticWorlds. ChinchillaMelonFestivalAustralia ChinchillainQueenslandisknownasthemeloncapitalofAustraliaandeveryotheryearinFebruaryitsresidentscelebratethegloriousredandjuicystickinessofwatermelonswiththisfour﹣dayfestivalwhichincludesmelonracesmelonskiingagiantmelonfoodfightandofcoursehavingyourfillofmelons.In2019thefestivalwillbeheldfromFeb. 14一17. 1Wheredoseafoodloversprefertogo? A.Munich. B.Menton. C.Chinchilla. D.Rockland. 2WhatisthemostpopularatOktoberfest? A.Bread. B.Potato. C.Pork. D.Beer. 3WhatisspecialaboutChinchillaMelonFestival? A.Itistheoldest. B.Itlaststhelongest. C.It'sheldeverytwoyears. D.IttakeplaceinAustralia'scapital.
△ABCD的内角ABC的对边分别为abc设sin2B+sin2C﹣sin2A＝sinBsinC． 1求A 2若求C．
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如果点Psinθcosθcosθ位于第四象限则角θ是
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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.
IfyouhaveeverfoundyourselflookingforyourkeysmisplacingyourcellphoneorwantingtokeeptrackofyourbicycleorcarthentheTrackRadevice装置thatworkswithyoursmartphonecreatedbyaCalifornia﹣basedcompanyisforyou!At﹩29.95eachnotliketheexpensiveGPSsystemsorwithTrackRPackpurchasedealsyoucan'taffordnottohaveone! Install安装thefreeTrackRapponyoursmartphone.Connecttheapptoyourdeviceandthenyouarereadytogo!SimplyattachtheTrackRtowhateveryoudon'twanttolose.Theentireprocesssettingituponlytakes5minutesorless. IfyouhavethehardTrackRyoucanjusthideitunderyourcar'sfloormat.Inthetrunkorsomewhereitwon'tbefoundifyourcargetsstolen.IfyouforgetwhereyouparkedyourcartakeoutyoursmartphoneandopentheTrackRapp.Taponthelostitemicononthescreenandtheappwilltellyouexactlywhereitis. Youcanalsoattachittoyourpet.Putitontheircollarandtheproblemofsearchingforthemastheyrunofftonearbyplaceswillbeover!Attachittoyourkeysandwalletandneverwasteaminutesearchingthewholehouseforit.TheaffordableTrackRevencomeswithadouble﹣sidedadhesive黏合剂soyoucansticktoyourlaptoporunderyourbikeseat.Trackdownandpunishthethieveswhostealyourexpensivethings!TheconvenienceandtheabilitytofindactuallyanyobjectmeansthatTrackRisoneofthemostusefularticlesthatyou'llfindforanyprice.Howeverthebestthingitcangiveispeaceofmindanditdoesn'tgetanybetterthanthat. 1WhatisParagraph2mainlyabout? A.HowtheTrackRworks. B.ThefeaturesoftheTrackR. C.WhytheTrackisinvented. D.TheadvantagesoftheTrackR. 2WhatcantheTrackRhelppeopledo? A.Walktheirpetsnearby. B.Recognizethethives. C.Seektheirmisplacedcar. D.Findthemaparkingplace. 3WhatcanweinferabouttheTrackR? A.It'sfarfromaffordable. B.It'sonsaleworldwide. C.Itcanbeeasilyfolded. D.It'ssmallinsize. 4What'sthebesttitleforthetext? A.TrackR﹣nolimits B.TrackR﹣﹣﹣noworries C.TrackR﹣﹣﹣youritemprotector D.TrackR﹣﹣﹣yourfinancialmanager
某中学举行高广播体操比賽共10个队参赛为了确定出场顺序学校制作了10个出场序号签供大家抽签高一1班先抽则他们抽到的出场序号小于4的概率为
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.
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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.
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
InmanyplaceslikeBritainandItalyifyouleavethehousewithoutyourwalletyou'llbeinatoughsituationallday.ButinChinayoucanenjoyyourdayjust1asmartphone. TheotherdayIsetout2seehowfaraphonewouldgetmeinthecountry'scapital.AdmittedlyIwassurprisedtodiscoverhow3convenienceitwas. IusedmyphonetocallataxitomeetmyChinesefriendGuYu4wouldguidemetogetaroundBeijing.Wepaidforbreakfastby5scanaQRcodeonthewindowofarestaurantsellingjianbingoneofChina'smostpopularstreetbreakfasts.Mypurchasecost6yuanand6takejustafewseconds.Atanearbycoffeeshop7itownerscannedaQRcodeonmyphone.AswesippedourcoffeeGuYupaidherhouseholdwaterbill.Sheusedthesamesimpleprocesstopayotherbillsandevenherrent.Wealsopaidbyphoneformovieticketstakeoutfoodshoppingandfor8deliver. IhaveknownfromGuYuthatfromtinystreetstandstolargechains9hugenumberofpeopleacceptmobilepayment10mostthroughpopularappsAlipayandWeChat.
Helicopterparentingreferstoastyleofparentswhoareoverfocusedontheirchildren. 1Forexampleitcanincreasefeelingsofloveandacceptance.Howeverhelicopterparentingmaybeharmfultochildren'sdevelopmentinthefollowingways. Decreasedconfidenceandselfesteem自尊.Themessagetheparents'overinvolvementsendstokidsismyparentsdon'ttrustmetodothisonmyown.2 Increasedanxiety.AstudyfromtheUniversityofMaryWashingtonhasshownthatoverparentingisassociatedwithhigherlevelsofchildanxietyanddepression. Undevelopedproblemsolvingskills.Ifparentsarealwaystheretocleanupachild'smessorpreventtheprobleminthefirstplacehowdoesthechildeverlearntodealwithlossdisappointmentorfailure?3 Strengthenedsenseofentitlement权利.Childrenwhohavealwayshadtheirsocialacademicandathleticlivesadjustedbytheirparentstobestfittheirneedscanbecomeaccustomedtoalwayshavingtheirwayandthustheydevelopasenseofentitlement. 4Parentswhoalwaystieshoesclearplatesandpacklunchesevenafterchildrenareabletodothetaskspreventtheirchildrenfrommasteringtheselifeskillsthemselves. Soparentsshouldletchildrenstruggleallowthemtobedisappointedandwhenfailureoccurshelpthemtoworkthroughit.5Remember:takingonestepbackfromsolvingchildren'sproblemswillhelpbuildtheindependentandselfconfidentkids. A.Weakenedlifeskills. B.Damagedlifeexperiences. C.Andthisdistrustleadstoalackofconfidence. D.Helicopterparentinghasmanybenefitsforchildren. E.Parentsshouldalsoletchildrendotaskstheyarephysicallyandmentallyabletodo. F.Makingyour3yearold'sbedsoundsreasonablewhilemakingyour13yearold'sbeddoesn't. G.Studiesfoundhelicopterparentingcanmakechildrenfeellessableindealingwiththestressesoflifeontheirown.
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