首页
试卷库
试题库
当前位置：
X题卡
>
所有题目
>
题目详情
与参数方程为（t为参数）等价的普通方程为（ ）
查看本题答案
包含此试题的试卷
高二下学期数学《》真题及答案
点击查看
你可能感兴趣的试题
参数方程θ为参数化为普通方程为.
已知直线l的参数方程是其中t为参数圆C.的极坐标方程为Ⅰ将圆C.的极坐标方程和直线l的参数方程转化为
参数方程为参数化成普通方程为
在平面直角坐标系xOy中直线l的参数方程为t为参数曲线C.的参数方程为θ为参数.试求直线l和曲线C.
参数方程中当为参数时化为普通方程为__
与参数方程t为参数等价的普通方程为．
已知直线l的参数方程是其中t为参数圆c的极坐标方程为Ⅰ将圆C.的极坐标方程和直线l的参数方程转化为普
与普通方程x2+y-1=0等价的参数方程为t为参数
在平面直角坐标系xOy中直线l的参数方程为t为参数曲线C.的参数方程为θ为参数.试求直线l和曲线C.
把下列参数方程化为普通方程并说明它们各表示什么曲线t为参数
在直角坐标系xOy中曲线M.的参数方程为α为参数若以直角坐标系中的原点O.为极点x轴的正半轴为极轴建
将参数方程t为参数化成普通方程为_________.
某曲线C.参数方程为t为参数点M.54在该曲线上.1求常数2求曲线C.的普通方程
参数方程α为参数化为普通方程为____________.
将参数方程θ为参数化为普通方程并指出它表示的曲线.
已知曲线C的参数方程为t为参数t＞0则曲线C的普通方程为.
在平面直角坐标系xOy中直线l的参数方程为t为参数曲线C.的参数方程为θ为参数.试求直线l和曲线C.
在平面直角坐标系中已知直线的参数方程是为参数以为极点轴正半轴为极轴的极坐标系中圆的极坐标方程为.Ⅰ写
在平面直角坐标系xOy中直线l的参数方程为t为参数曲线C.的参数方程为θ为参数试求直线l与曲线C.的
已知直线的参数方程为t为参数曲线C.的参数方程为θ为参数.1将曲线C.的参数方程化为普通方程2若直线
热门试题
更多
Mr.PeterJohnsonagedtwenty﹣threebattledforhalfanhourtoescapefromhistrappedcaryesterdaywhenitlandedupsidedowninthreefeetofwater.Mr.Johnsontooktheonlyescaperoute﹣﹣throughtheboot行李箱. Mr.Johnson'scarhadfinishedupinaditch沟渠atRomneyMarsinKentafterskiddingoniceandhittingabank.FortunatelythewaterbegantocomeinonlyslowlyMr.JohnsonsaidIcouldn'tforcethedoorsbecausetheywerejammedagainstthewallsoftheditchanddarednotopenthewindowsbecauseIknewwaterwouldcomefloodingin. Mr.JohnsonasweetsalesmanofSittingHomeKentfirsttriedtoattracttheattentionofothermotoristsbysoundingthehornandhammeringontheroofandboot.Thenhebeganhisstruggletoescape. LaterhesaidItwasreallyahalfpennythatsavedmylife.ItwastheonlycoinIhadinmypocketandIusedittounscrewthebackseattogetintotheboot.Ihammereddesperatelywithahammertryingtomakesomeonehearbutnohelpcame. Ittooktenminutestounscrewtheseatandafurtherfiveminutestoclearthesweetsamplesfromtheboot.ThenMr.Johnsonfoundawrenchandbegantoworkonthebootlock.Fifteenminutespassedby.ItwastheonlychanceIhad.FinallyitgavebutassoonasImovedthebootlidthewaterandmudpouredin.Iforcedtheliddownintothemudandscrambledclearasthecarfilledup. HishandsandarmscutandbruisedMr.JohnsongottoBeckettFarmnearbywherehewaslookedafterbythefarmer'swifeMrs.LucyBates.TremblinginablankethesaidThatthirtyminutesseemedlikehours.Onlythetipsofthecarwheelswerevisiblepolicesaidlastnight.Thevehiclehadsunkintotwofeetofmudatthebottomoftheditch. 1Inwhichsectionofanewspapercanwereadthisarticle? A.Bookreview B.Newsreport C.Campuslife D.Continuedstory 2TheunderlinedsentenceinParagraph5Finallyitgavemeansthat. A.luckilythedoorwastornawayintheend B.atlastthewrenchwentbroken C.thelockcameopenafterallhisefforts D.thechancewaslostatthelastminute 3Itcanbeinferredfromthepassagethat. A.theditchwasalongaquietcountryroad B.theaccidenthappenedonaclearwarmday C.thepolicehelpedMr.Johnsongetoutoftheditch D.Mr.Johnsonhadatenderwifeandwaswellattended
OurMuseumsGalleriesandZoo 19world﹣classmuseumsgalleriesandazoo TheSmithsonianofferselevenmuseumsandgalleriesontheNationalMallandsixothermuseumsandtheNationalZoointhegreaterNationalCapitalArea.InNewYorkCityweinviteyoutotourtwomuseumsinhistoricsettings. NotnearaSmithsonianmuseum?Lookforexhibitionsandmuseumsinyourcommunity.Herewehavelistedsomeplacestovisit Tips&Guidelines StopatanySmithsonianmuseuminformationdeskwherefriendlyandknowledgeablestaffandvolunteerscanassistyouinplanningyourvisit. ServiceanimalsarewelcomeatthemuseumsandtheNationalZoo.Petsarenotpermitted. Lunchesshouldbeproperlyclosedorstoredinlockersduringyourvisit. 1TheSmithsonianoffersalltheseEXCEPT. A.galleries B.concerts C.museums D.zoos 2Ifyouareinterestedinanimalsyoucan. A.goto1661PennsylvaniaAvenueNWWashingtonDC B.goto8thandFStreetsNWWashingtonDC C.visitthemuseum11a.m.onChristmas D.visitthezooatweekendsonJune25 3Toarrangeyourvisitbetteryoucan. A.havelunchduringyourvisit B.takeyourpetsalongwithyou C.askthestaffandvolunteersforhelp D.fillinanapplicationformbeforeyourvisit
TheMonkeesbupabout1970buthappilytheyreunitedinthemid﹣1980﹩.
LearningFastandDeep Overthepastfiveyearsresearchersinartificialintelligencehavebecometherockstarsofthetechnologyworld.AbranchofAIknownasdeeplearningwhichusesneural神经的networkstoscanthroughlargevolumesofdatalookingforpatternshasprovensousefulthatskilledpractitionerscancommandhighsix﹣figuresalariestobuildsoftwareforAmazonAppleFacebookandGoogle. ThestandardrouteintothesejobshasbeenaPhDincomputersciencefromoneofAmerica'stopuniversities.Earningonetakesyearsandrequiresapersonalitysuitedtoacademiawhichisrareamongmorenormalfolk. Thatischanging. Lastmonthfast.aianon﹣profiteducationorganizationbasedinSanFranciscokickedoffthethirdyearofitscourseindeeplearning.Sinceitsfoundationithasattractedmorethan100000studentsaroundtheglobefromIndiatoNigeria.ThecourseandotherslikeitcomewithasimpleideathereisnoneedtospendyearsobtainingaPhDinordertopractisedeeplearning.Creatingsoftwarethatlearnscanbetaughtasacraftnotasahighintellectualpursuittobeundertakenonlyinanivorytower.Fast.ai'scoursecanbecompletedinjustsevenweeks. TomakeitaccessibletoanyonewhowantstolearnhowtobuildAIsoftwareistheaimofJeremyHowardwhofoundedfast.aiwithRachelThomasamathematician.Hesaysschoolmathematicsissufficient.No.Greek.LettersMr.Howardintonespoundingthetablewithhisfistforpunctuation. SomeexpertsworrythatthiswillserveonlytocreateafloodofunreliableAIsystemswhichwillbeuselessatbestanddangerousatworst.IntheearliestdaysoftheInternetonlyaselectfewnerdsnamelycomputerholicswithspecificskillscouldbuildapplications.Notmanypeopleusedthem.ThentheinventionoftheWorldWideWebledtoanexplosionofwebpagesbothgoodandbad.ButitwasonlybyopeninguptoallthattheInternetgavebirthtoonlineshoppinginstantglobalcommunicationsandsearch.IfMr.HowardandothershavetheirwaymakingthedevelopmentofAIsoftwareeasierwillbringforthanewcropoffruitofadifferentkind. 1Whatcanwelearnaboutdeeplearning? A.Itreplacesartificialintelligence. B.Itattractsrockstarstopractice. C.Itscanspatternsforlargecompanies. D.Ithelpstechnicianstocreatesoftware. 2Fast.aiisanorganizationthat. A.ensuresonetoobtainaPhD B.teachescraftinivorytower C.offersacourseindeeplearning D.requiresweekstoapply 3TheunderlinedwordsNo.Greek.LettersinParagraph5meansdoingfast.aicourseis. A.easy B.difficult C.interesting D.boring 4Itcanbeinferredfromthelastparagraphthat. A.itisquitereliableforanyonetograspartificialintelligence B.theInternethasbroughtforthafloodofuselessAIsystems C.openinguptoallleadstoinstantglobalsearchandonlineshopping D.simplifyingsoftwaredevelopmentmayresultinunexpectedoutcomes
ItwasMother'sDaybuttheyoungmotherwasalittleunhappybecauseshewas800milesawayfromherparents.Inthemorningshephonedhermother1wishherahappyMother'sDayandhermothertoldheraboutthebeautifullilacs丁香inthegarden.2latethatdaywhenshetoldherhusbandaboutthelilacshesaidIknowwherewecanfindallthatyouwant.Getthechildrenandcomeon.Sotheywent3drivedownthecountryroads. Thereonasmallhilltheysawalotof4beautypurplelilacs.Theyoungwomanranquicklytoenjoytheflowers.Carefullyshepickedafewhereandafewthere.Ontheirwayhometherewasasmile5herface.ziliaoqun700292070 Whentheywerepassinganursinghome养老院theyoungwomansaw6oldgrannysittinginachair.Shehadnochildrenwithher.They7stopthecarandtheyoungwomanwalkedtotheoldwomanputtheflowersinher8handandsmiledather.Theoldgrannythankedheragainandagain.Shesmiledhappilytoo. Whentheyoungmothercamebacktohercarherchildrenaskedher9isthatoldgranny?Whydidyougiveourflowerstoher? Idon'tknowher10theymothersaid.Butit'sMother'sDayandshehasnochildren.IhaveallofyouandIstillhavemymother.Justthinkhowmuchthoseflowersmeanttoher.
已知函数fx＝sinxcosx+cos2x． 1求y＝fx的最小正周期并求其单调递减区间 2△ABC的内角ABC所对的边分别为abc若fA＝且A为钝角a＝2求△ABC面积的最大值．
在数列{an}中a1＝2an+1＝an+n+1则a5＝．
AphotographthatonehastakenofoneselftypicallywithasmartphoneorwebcamanduploadedtoasocialmediawebsiteisthedefinitionofselfieintheOxfordEnglishDictionary.Infactitwasn'teveninthedictionaryuntilAugustoflastyear.Itearneditsplacetherebecausepeoplearenowsoobsessedwith对……痴迷selfies﹣wetakethemwhenwetryonanewhatplaywithourpetsorwhenwemeetafriendwhomwehaven'tseeninawhile. Butisthereanyscientificexplanationforthisobsession?WellyoushouldprobablyaskJamesKilneraneuroscientist神经系统科学家atUniversityCollegeLondon. Throughourlifetimewebecomeexpertsatrecognizingandinterpretingotherpeople'sfacesandfacialexpressions.IncontrastaccordingtoKilnerwehaveaverypoorunderstandingofourownfacessincewehavelittleexperienceoflookingatthem﹣wejustfeelthemmostofthetime. ThishasbeenprovedinpreviousstudiesaccordingtotheBB24C. Kilnerfoundthatmostpeoplechosethemoreattractivepicture.Thissuggeststhatwetendtothinkofourselvesasbetter﹣lookingthanweactuallyare.TofurthertesthowweactuallyperceiveourownfacesKilnercarriedoutanotherstudy.Heshowedpeopledifferentversionsoftheirownportrait﹣theoriginalonethathadbeeneditedtolooklessattractiveandonethatwasmademoreattractive﹣andaskedthemtopicktheversionwhichtheythoughtlookedmostlikethem.Theychosethemoreattractiveversion. Butwhatdoesitsayaboutsettles?Wellisn'tthatobvious?Selfiesgiveusthepowertocreateaphotograph﹣bytakingitfromvariousangleswithdifferentposesusingfilters滤色镜andsoon﹣thatbettermatchesourexpectationswithouractualfaces. Yousuddenlyhavecontrolinawaythatyoudon'thaveinnon﹣virtual非虚拟的interactionsKilnertoldtheCanada﹣basedCTVNews.Selfiesallowyoutokeeptakingpicturesuntilyoumanagetotakeoneyou'rehappywithheexplained. 1Whatisthepassagemainlyabout? A.Thedefinitionandfunoftakingselfies. B.Theexplanationofwhypeoplelovetakingselfies. C.Howtakingselfiesinfluencespeople'sdailylives. D.Howtointerpretpeople'sfacialexpressionsintheirselfies. 2TheunderlinedwordperceiveinParagraph5canbereplacedby. A.interpret B.beautify C.choose D.destroy 3AccordingtoKilnerpeopleliketakingselfiesprobablybecausetheythink. A.itisagoodchancetolearnmoreabouttheiractualfaces B.itisawaytorespondtoothers'facialexpressionscorrectly C.itenablesthemtointeractwiththeirfriendsinsocialmedia D.itallowsthemtosatisfytheirexpectationswiththeirappearances
一个长方体长宽分别为54且该长方体的外接球的表面积为50π则该长方体的表面积为
Withmoreforestsdhugequantitiesofgoodeartharebeingwashedawayeachyear.
Ihavemadegreatprogressinmath.IbegintounderstandanoldsayingNopainsnog.
设函数fx＝m+1x2﹣m2x+m﹣1． 1当m＝1时解关于x的不等式fx＞0 2若关于x的不等式∫x＜0的解集为求m的值
TheSurprisinglyEasyTrickThatCanHelpYouUseYourPhoneaLittleBitLess ThefirstthingIdointhemorningsislookatmyphone.That'smainlybecausemyphoneismyalarmclockbutoncemyeyesareopenandthatscreenislitupinmyhandsit'sanawfullyshorttriptocheckingemailsandperusingheadlines.1Myemailsthatearlyinthemorningaremainlyjunkandtheheadlineswon'tchangemuchbeforeI'vebrushedmyteethandpouredacupofcoffeeright? MywifesaysI'maddictedtomyphone.2I'mnotterriblyactiveonsocialmediabutIdoenjoymesomeidlescrollingenjoyplayingthemobilephone.Andwowdothesetechcompaniesknowhowtokeepthosethumbsconstantlyswipingup. 3WhileIthinkwe'reprettygoodaboutlimitingherscreentimeitwouldseemthattechnologyhashaditshooksinmefromthestart.SoIdecidedtotrylooseningmyphone'sgrasponmyattentionbyswitchingthescreentoblackandwhite. Changingthedisplaytoblackandwhiteisveryeasy.InyouriPhone'ssettingschooseGeneralthenAccessibility.NextchooseDisplayAccommodationsthenColorFilters.Tapthetoggleonandalistoffiltersappears.4 ButnoonewantstogothroughallthiseverytimetheywanttoturncolorbackontocheckoutanInstagramstory.Clearlyyoudon'talwayswantyourscreentobeblackandwhite.Afteralltherewillunavoidablybephotostoviewandvideostoshare.5IntheAccessibilitymenutapAccessibilityShortcutandchooseColorFilters.Nowpressingthehomebuttonthreetimeswillswitchyourdisplaytocolorandthenbackwithanotherthree. A.There'snoreasonformetobedoingthis. B.We'vegotathree﹣year﹣oldchild. C.ChooseGrayscaleandyou'reallset. D.Itcanhelpyouuseyourphonealittlebitless E.IdisagreebutIcandefinitelystandtospendlesstimelookingatit. F.Herecomesasurprisinglyeasytrick. G.Thatiswhatmakessettingashortcutnecessary.
Heenteredtheroomwithoutp.
Hefoundhimself包围bykindness.
△ABC中内角ABC所对的边分别是abc且a+b2﹣c2＝4C＝120°则ab的值为．
若cosα﹣＝cos2α则sin2α＝
假设你是红星中学高三学生李华请根据以下四幅图的先后顺序写一篇英文周记记录上周你和同学参与国家博物馆庆祝改革开放四十周年大型展览Celebrating40thAnniversaryofReformandOpening﹣up志愿者活动的全过程. 注意词数不少于60提示词国家博物馆theNationalMuseumofChina
Whetheryoulikeitornotasstudentsyouhavetolivewithroommatesaftergoingtoschooloruniversity.Havingaroommatecanbeoneofthebestexperiencesoreasilyoneoftheworst.1 Herearefivetipsforyoutofollowtoavoidthecommonmistakesthatmakegoodroommaterelationshipsworse. Talkthingsout.2Ifsomethinghappenssitdownwithyourroommatesandhaveaface﹣to﹣faceconversation.Complainingaboutyourroommatesbehindtheirbackscreatesnothingbutbadsituationsandgeneralunhappiness. 3Someroommatesbecomethebestoffriendsandsomedon't.Don'tputpressureonyourselforyourroommatetoreachthislevelespeciallywhenyoufirstmeet.Rememberyouaretryingtomakeanewfriendnotfrightenyourroommateaway.Andifyouroommatedoesn'tendupbeingyourbestfriendthereisnoneedtoworryaboutit. Cleanupafteryourself.Oratleastkeepyourthingsonyourside.4Butbeingconsiderate考虑周到的withwhereyouputyourownstuff东西willhelpyouavoidthearguments. Askbeforeyoutake.Thisappliesto适用于foodclothesandanythingelsethatyoudon'town.5Evenifyoubothagreetoshareeverythingyoushouldstillask. A.Don'texpecttobebestfriends. B.Communicationisofvital至关重要的importance. C.Youdon'tneedtokeeptheroomcleanandorganizedallthetime. D.Roomscanbereallyeasyforamesstopileup. E.Ifyouwanttohaveagoodrelationshipwithyourroommateitallstartswithyou. F.Trytomakeyourroommatesyourbestfriends. G.Showyourroommatethatyouhaverespectforhisorherthings.
有一款手机每部购买费用是5000元每年网络费和电话费共需1000元每部手机第一年不需锥修第二年推修费用为100元以后每一年的维修费用均比上一年增加100元．设该款手机每部使用x年共需维修费用fx元总费用gx元总费用一购买费用+网络费和电话费十维修费用 1求函数fxgx的表达式 2这款手机每部使用多少年时它的年平均费用最少
假设你是南阳中学的学生李华将参加主题为Let'spickupabookandread的英语演讲比赛.请你写一份演讲稿主要内容包括 1.目前很多学生课余时间沉溺于网络远离书本导致记忆力减退对学习失去兴趣等问题. 2.阅读的益处如开阔视野增强理解力提高成绩等. 注意1.词数100左右.演讲稿开头和结尾已给出但不计入总词数. 2.可适当增加细节以使行文连贯. Goodmorningeveryone I'mLiHuafromNanyangMiddleSchool.ThetopicofmyspeechisLet'spickupabookandread. Thankyou!
IntheUSAColumbusDayisinmofthearrivalofChristopherColumbusintheNewWorld.
一个几何体的三视图如图所示则该几何体的体积为
A AtmyfirstclassintheForksHighSchoolMr.BannermyEnglishteachersentmetoanemptydeskatthebackwithout1introducemetotheclass.Itwasharderformynewclassmates2stareatmeinthebackbutsomehowtheymanaged.Ikeptmyeyesdownonthereadinglisttheteacherhadgivenme.Itwas3fairbasicBronteShakespeareChaucerFaulkner.I'dalreadyreadeverything.Thatwascomforting…andboring. B Yourteethmaybepartofyoursmile4theyhaveamoreimportantjob﹣theyrethefirststepintheprocessofdigestion.Youhavethree5kindofteeth.Intheveryfrontofyourmouthareeightflatthinteethcalledincisors.Theyareusedforcuttingandbitingfood.Nexttothesearepointedteethcalledcanines6alsohelpyoutearfood.Theremainingteetharemolars.Theseteethhaveflattopsforcrushingandgrindingthefood. C TheBeijingVanke﹣ShijinglongSkiResortislocated7YanqingDistrictanationaldemonstrationareaforecologicalconstruction.WithLongqingGorgetoitseastandGuantingReservoirtoitswestithasfreshairandan8impressenvironment.9buildin1999itwasthefirstlargeskiresorttobebuiltnearBeijing.In2016amassiverenovationproject10startbyVanketheBeijingBadalingTourismGeneralCompanyandtheoriginalBeijingShijinglongSkiResort.
It'sasadandfamiliarvoicethatweoftenhearinbigcitiesCanyousparesomechange? Usuallywhenfacedwiththatparticular1IhavefeelingsofguiltifIpassby2givingacoinortwo. Ihadthatfeeling3inVenicewhileonatourofItaly'sfamoussitesin2006.Ihadtakenrefugefromthe4inaquietcafé.Outsidetherewasanoldwomankneelingonthehardancientpavingstones5. Steady6oftouristswerewalkingpasther.Ayoungbackpackerstoodawayfromthecrowd7drinkinginthescenerybutInoticedtheyoungtravelerwasalso8theoldwoman. Atouristgroupwalkedalongthestreet9thewomanandwalkedon.10groupoftouristsarrivedandwalkedpasttheoldlady.Thebackpackerwatched11everybodyelsewentontheirwayfocusedonthe12aroundthem.ThenIwaspreparingtoleavewhenIcaughtsightofthebackpackersteppingforwardand13somemoneyinthewoman'scup.Hedidthissomewhat14justbeforethearrivalofanothertouristgroup.AsI15theleaderofthegroupstoppedandputsomemoneyinthecup.Havingbeenshownthewayothertouristsfollowedsuitand16somemorecoinstothecup. Hisworkdonetheyoungmanwalkedovertotheoldbeggar﹣womanpattedherontheshoulderandsaidIhopethat17alittle. Idon'tknowifthewomanunderstoodhisEnglishor18whathadjusthappenedbutIdid. Iplacedsomemoneyinthewoman'scupandcontinuedmytravels19afterwitnessingsuchan20actofkindness. 1A.sound B.question C.excuse D.command 2A.beyond B.after C.without D.before 3A.manytimes B.sometimes C.onlyonce D.onceagain 4A.crowds B.families C.streets D.signs 5A.singing B.crying C.begging D.trembling 6A.streams B.packs C.masses D.groups 7A.simply B.seemingly C.similarly D.specially 8A.showing B.following C.checking D.observing 9A.glancedat B.laughedat C.rushedat D.staredat 10A.One B.More C.Another D.Other 11A.if B.since C.because D.as 12A.stones B.sights C.signs D.tourists 13A.lending B.borrowing C.placing D.taking 14A.accidentally B.successfully C.deliberately D.cheerfully 15A.watched B.shown C.understood D.walked 16A.changed B.charged C.found D.added 17A.measures B.helps C.explains D.matters 18A.recognized B.caught C.realized D.figured 19A.pleasant B.annoyed C.disappointed D.delighted 20A.beautiful B.admirable C.pure D.accurate
Abdietandregularphysicalactivitywillhelpyoukeepfit.
ThemusicwaswrittenbyAbingafolkmwhowasborninthecityWuxiin1893.
BothEnglishandFrenchareolanguagesinCanada.
Tobehalotofpeopleattachgreatimportancetobecomingrichandfamous.
Althoughitisoftencalledthekoalabearthislovelyanimalisnotactuallyabearatall.Itisamarsupial有袋目哺乳动物andlikekangaroosafemalekoalacarriesherbabyinherpouch育儿袋foraboutsixmonths. KoalasliveinfourstatesonlyineasternAustraliawheretheeucalyptustrees桉树theylovearemostplentiful.Infacttheyrarelyleavethesetreestheirsharpclawseasilykeepingthemhighupintheair. Duringthedaytheysleepforupto18hours.Whennotasleeptheyfeedoneucalyptusleavesespeciallyatnight.Koalasdonotdrinkmuchwaterandtheygetmostoftheirwaterfromtheseleaves.Eachanimaleatsalargeamountforitssize﹣abouttwoandahalfpoundsofleavesadayevenstoringsnacksofleavesinpouches. Thekoalabearswerewidelyhuntedduringthe1920sand1930sandtheirpopulationsdecreasedsuddenly.Helpedbyreintroductiontheyhavereappearedovermuchoftheirformerrangebuttheirpopulationsaresmaller.Koalasneedalotofspace﹣aboutahundredtreesperanimal﹣whichisapressingproblemasAustralia'swoodlandscontinuetogetsmallerbecausethetreestheyliveonarebeingcutdowntomakefarms.Alsoforestfirescausedbyheatwavesaredestroyingtheforeststhekoalaslivein. Ithasbeenestimated估算thatthereareonly100000koalasleftinthewildwiththelowestestimatesbeingnomorethan43000.ThekoalacanonlyeateucalyptusleavesandlivesnowhereelseexceptAustraliasoinordertosurvivehumaneffectonitslimitedenvironmentmustbecontrolledorthisattractivecreaturefacescertainextinction. 1Whyarekoalasindangerofdyingoutaccordingtothetext? A.Manyofthemdiedintheforestfire. B.Theycan'tbeusedtotheglobalwarming. C.Theirlivingenvironmentisgraduallybeingworsened. D.Farmersareburningtheeucalyptustreesthatkoalasliveon. 2Whathappenedduringthe1920sand1930s? A.Koalasfacedgreatdanger. B.Koalagotwellprotected. C.Koalas'populationfellslowly. D.Koalahadenoughspacetolivein. 3Whatwilltheauthormostprobablytalkaboutnext? A.Howtoincreasekoalas'population. B.Howtomakethebestofthelimitedenvironment. C.Howtohelpkoalasgetusedtothenewlivingenvironment. D.Howtoreducehumaneffectonkoalas'livingenvironment.
热门题库
更多
高二上学期英语
高二上学期生物
高二下学期数学
高二上学期化学
高二下学期物理
高三下学期物理
高三上学期物理
高三上学期生物
高三上学期化学
高二下学期化学
高二下学期生物
高三下学期生物
高三下学期化学
高三上学期英语
高二下学期英语
教案备课库
湘公网安备 43130202000226号