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点P（2，﹣5）关于y轴的对称点的坐标是（ ）
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点M.﹣1﹣2关于y轴的对称点坐标是__________.
已知点P.关于x轴的对称点为a1关于y轴的对称点为-2b则点P.的坐标是.
在直角坐标系中已知点A.32.作点A.关于y轴的对称点为A.1作点A.1关于原点的对称点为A.2作点
点24关于y轴的对称点的坐标是.
点P.32关于y轴的对称点的坐标是_________.
已知点P.关于x轴的对称点为a－2关于y轴对称点为1b那么点P.的坐标为______________
点A.－2aa－1在x轴上则A.点的坐标是__________A.点关于y轴的对称点的坐标是____
在空间直角坐标系中已知点P.xyz给出下列四条叙述①点P.关于x轴的对称点的坐标是x－yz②点P.关
3
2
1
0
点P.关于x轴的对称点P1的坐标是4﹣8则P.点关于y轴的对称点P2的坐标是
（﹣4，﹣8）
（﹣4，8）
（4，8）
（4，﹣8）
点M.3－4关于x轴的对称点的坐标是关于y轴的对称点的坐标是.
点A.－12关于y轴的对称点坐标是点A.关于x轴对称的点的坐标为
已知点P.32则点P.关于y轴的对称点P.1的坐标是________点P.关于原点O.的对称点P.2
在平面直角坐标系中点A.的坐标是2－3作点A.关于x轴的对称点得到点A.'再作点A.'关于y轴的对称
在平面直角坐标系中点A的坐标是2﹣3作点A关于x轴的对称点得到点A′再作点A′关于y轴的对称点得到点
已知点P.关于x轴的对称点P.′的坐标是23那么P.关于y轴对称点P.的坐标是________.
已知点P.－31则点P.关于y轴的对称点的坐标是点P.关于原点O.的对称点的坐标是
已知点P32则点P关于y轴的对称点P1的坐标是点P关于原点O的对称点P2的坐标是.
在直角坐标系中已知点A.32.作点A.关于y轴的对称点为A.1作点A.1关于原点的对称点为A.2作点
点p关于y轴对称的点坐标为－2－3它关于x轴的对称点为______________
如果抛物线y=ax2-2ax+5与y轴交于点A.那么点A.关于此抛物线对称轴的对称点坐标是_____
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Measuringupto10.5feetinlengththewesterngreenmamba曼巴蛇isthesecondlongestsnakeinAfricawiththeblackmambabeingthefirst.Itisalsothemostagile敏捷的snakeinthemambafamily.Theircolorischangeablewhichhelpsthemjointheirenvironment.Anotherdistinctivefeatureofthesnakeisitslongtailwithasharppoint. Thewesterngreenmambalivesinrainforests.Beinganarborealspeciesthesesnakesspendmostoftheirtimemovingamongthetreetops.Howevertheyusuallyleavetheirtreestopursueapotentialmealontheground.Thewesterngreenmambaismostlyactiveatdaybutcanalsobeseenhuntingatnight. Thedietofawesterngreenmambaconsistsofbirdsandavarietyofsmallmammalssuchassquirrelsmiceandevenbats.Thesesnakeswillapproachtheirtargetswiththehelpoftheirnaturalskincolor.Whentheyarecloseenoughtheywillbitetheirvictimsandinjectthemwithvenom毒液quickly.Oncethetargethasdiedtheweaterngreenmambawillswallowitsmealwhole.Iffacedwithdangerthesesnakeswilltrytorunaway.Iftheyarecorneredhowevertheywillbecomeextremelyaggressiveandstrikewiththeirsharpteethrepeatedly.Thefemaleweaterngreenmambaistheonewholayseggs.Shewilllayeggsanywhere.Theyoungsnakesarecompletelyindependent.Themotherandfatherplaynopartinraisingthebabysnakes.Thebabiesarebornwitheverythingtheyneedtosurviveinthewilderness.Theywillhavealmostnonaturalpredators捕食者toworryaboutwhentheyreachadulthood. 30.Whatdoestheunderlinedwordarborealinthesecondparagraphprobablymean? A.Mainlyfeedigonmeat. B.Mainlyfeedingonplants C.Livingontreesmostofthetime D.Livinginthegrassmostofthetime 31.Whenisthewesterngreenmambamostaggressive? A.whenithastoprotectitseggs B.Whenitissearchingforfood. C.Whenitapproachesitstarget D.Whenitgetsnowaytoescape 32.Whatcanwelearnfromthetext? A.ThewesterngreenmambacanbefoundalloverAfrica. B.ThewesterngreenmambaisthelongestsnakeinAfrica. C.Thewesterngreenmambaoftenswallowsliveanimalwhole. D.Thebabywesterngreenmambadoesn'tneedcare.
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Weallwanttogivegiftsthatareappreciated.Thattakestimeandtalent.Hereareafewstepsthatwillhelpyouchoose. Preparetobuygiftsinadvance Choosingperfectgiftsforyourfriendsandfamilystartsbeforeyoureachastore.Youwillbuythebestgiftsforeachpersonbydoingyourhomeworkinadvance. Watchwithyoureyes IfyouarearoundthepersonoftenwatchwhathepicksupinstoreandwatchesonTVorwatchwhathelooksatinnewspapers.Thosecluescanbetranslatedintogiftsatanothertime. Tuneinyourfriendswithyourears Adirectgiftmethodistoaskthepersonwhathewants.Thenlistentowhatissaid. Asksomeoneelseaboutgifts Asksomeoneclosetotherecipient接受者forafewgiftsuggestions.Maybetheywillevengowithyoutobuythegift.Betteryetmaybetheywillbuythegiftforyou! Makealistofpotentialgifts Beforeyoueverleavehomemakealistofpotentialgiftsforthisperson.Infactcheckforgiftideasonlinefirst.Maybewithalittleluckonlineyouwon'tevenhavetoleavehome. Whenyougivesomeoneagiftitismorethanapresent.Whatyougivehimshowsyourfeelingforhimoryourthoughtsofhim.Whenyougivesomeoneagiftthatletshimknowhowyoufeelabouthimyouaregivingagifttherecipientwilltreasureregardlessofthepriceofit. Ifyouhavesuggestionsaboutchoosingtheperfectgiftpleaseletusknowhere.Thankyou. 60.Thepassagemainlytellsthereader. A.whatchoosinggiftscosts B.howtochooseperfectgifts C.whatgiftsyoumaygivesomeone D.howusefulgiftsaretoyourfriend 61.WhenyoubuyagiftforyourfriendyoushouldNOT. A.askhimwhathewantsandfollowhiswords B.preparetobuythegiftinadvance C.choosethegiftonyourown D.asksomeoneclosetotherecipientforadvice 62.ThetitleWatchwithyoureyessuggests. A.stayingwiththerecipientasoftenaspossible B.alwaysdoingshoppingwiththerecipient C.watchingTVorreadingnewspaperswiththerecipient D.watchingtherecipient'slikesordislikes 63.Fromthegiftyougivetheperson. A.hecanknowhowyoufeelabouthim B.youcanreceivemoregiftsthanwhatyougivehim C.hecandecideifit'sworthtreasuringbytheprice D.hecanrealizeyourfeelingforthegift.
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在哺乳动物体细胞核中除一条X染色体外其余的X染色体高度螺旋化失活成为巴氏小体如图所示．失活现象发生在胚胎发育的早期并且在体细胞中这种失活是不可逆的．巴氏小体的数目及形态可通过显微镜观察通常位于间期核膜边缘．请回答 1利用显微镜观察巴氏小体可用染色． 2体育运动会上采用巴氏小体方法进行性别鉴定理由． 3色盲是一种常见的单基因遗传病单基因遗传病是指受控制的遗传病．一对色觉正常的夫妇生了一个色盲女儿请分析其原因该女儿与色觉正常的男性婚配生一个色觉正常儿子的几率为．
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Ihadreachedtheairportabout30minutesago.Itwasavery36threedaysformewithlotsofmeetings.SoIwasgladtohavethe37timetomakemynotesonwhatI38todothefollowingday.Butthencamethe39thatmyflighthadtobe40becausetherewasaproblemwiththeplane. WhenIsatwaitingformy41tobecalledIthoughtaboutmylastmeetingoftheday.Itwasnotabusinessmeetingbutratheraveryenjoyable42withanoldbusinessfriendIhadnotseenforover12years.Ourlunchwasspentrecallingthegoodtimes43experiencingwhathadhappenedinourlivesoverthelast12years.Webothlaughedandsmiledaswerecalledthegoodtimesandthegreatexperienceswehad44together.Attheendofourtimetogetherwebothsaidhowmuchwehad45itandthatwemustdoitagain. Itwasgreattohavethisadditional另外的timetoreplayinmy46allthatwehadtalkedabout.I47howimportantitwastoregularlyrecallthegoodtimesinourlife.Iwasluckyenoughtohavehadthechancetotakeashort48andsharethegoodthingsthathadhappenedinmylifeover12years. Itwasalittlelikelookingatanoldphotoalbum49inacupboardinyourhouse.Beforeyoureyestherearelotsofwonderful50thattakeyoubacktotimesandplacesandmostimportantlytothosepeoplewhoareinthe51. Myflighthomewasfinally52threehourslater.IsmiledasI53theplaneandrealizedthatIwasnotatall54aboutthedelayintheflightasIhadbeenabletospendtheti 36.A.important B.busy C.quick D.useful 37.A.pleasant B.satisfying C.happy D.extra 38.A.had B.failed C.needed D.asked 39.A.announcement B.radio C.opening D.speech 40.A.waited B.cancelled C.taken D.delayed 41.A.flight B.turn C.name D.order 42.A.agenda B.lunch C.party D.discussion 43.A.asfaras B.aslongas C.aswellas D.asgoodas 44.A.spent B.met C.managed D.shared 45.A.got B.enjoyed C.made D.paid 46.A.thought B.spirit C.flight D.mind 47.A.decided B.enjoyed C.realized D.expected 48.A.way B.cut C.method D.break 49.A.stored B.included C.set D.lain 50.A.celebrations B.memories C.awards D.presents 51.A.cupboard B.books C.childhood D.photos 52.A.shouted B.phoned C.called D.sent 53.A.left B.boarded C.jumped D.reached 54.A.upset B.happy C.crazy D.surprised 55.A.passing B.killing C.recalling D.picking
EmilyMycolleaguessayIshouldgethealthinsurance.61doyouthinkofthissuggestionPaul? PaulIthinkit'sreallynecessaryEmily.Thoughyouhavetospendsomemoneyitsavesmoneyinthelongterm.62wemayfallillattimes.Iwillgiveyoumyinsuranceagent'sbusinesscardifyouwant. EmilyInGermanywehaveanationalprogram63provideallcitizenswithfreehealthinsurance.Buthereyouhavenothing. PaulYesIknow.Manycountrieshavenationalhealthinsurance.Americadoesn't. EmilyWhy?As64asIknowtheUSistherichestand65powerfulcountryintheworldisn'tit? PaulWell66influencebyAmericaculturewethinkprivatecompaniescandothingsbetter67thegovernment.Sowerelyonprivatecompaniesforinsurance. EmilyButisn'tthatexpensive? PaulYou'reright.Thehealthsystem68criticizebymanypeopleovertheyears.Theysayitisnotfairtopoorpeople. EmilyButwhat'syouropinion? PaulPersonallyagoodbodyismorereliablethanhealthindurance.That's69Isetasidesometimeforexerciseeveryday70busyIam. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.
假定你是李华从小喜爱大熊猫一直通过有关网站关注几年前在美国动物园出生的大熊猫苏琳和她的母亲白云.现在苏琳即将过生日.请根据以下要点给动物园工作人员写一份信 内容1.自我介绍2.祝贺苏琳生日3.感谢工作人员4.索取苏琳的生日照片. 要求1.只能用5个句子表达全部内容 2.要使用多种时态 3.开头语已经为你写好. DearSir/Madam GreetingsfromChina!
下列有关叶绿体和线粒体内部分代谢活动的叙述正确的是
Maggiehasbeenluckytofindajobshelovesandshegetswellpaidforit. A.soonerorlater B.what'smore C.asaresult D.moreorless
三孢布拉霉菌能用来生产胡萝卜素但该菌株的高产性状容易退化需要定期筛选出高产菌株研究表明菌体细胞内含有可将无色的TTC还原为红色复合物的物质且菌体细胞内该物质的含量越高还原能力越强胡萝卜素合成能力也越强．结合下列筛选菌株及提取胡萝卜素的流程图回答问题 三孢布拉霉菌→梯度稀释→涂布到含TTC的培养基上→挑取单菌落→扩大培养→收集菌丝并处理→萃取→鉴定 1胡萝卜素的提取方法有从植物中提取等等．上述流程图中提取到胡萝卜素后鉴定一般要用法．胡萝卜素能够治疗夜盲症干皮症等是因为夜盲症干皮症等疾病是由于缺少维生素A而引起的而1分子的β﹣胡萝卜素可被氧化分解成2分子．根据胡萝卜素的理化性质分析为了让胡萝卜素更容易被人体吸收炒胡萝卜时要多加些． 2流程图中将菌液涂布到含TTC的培养基上目的是筛选出合成胡萝卜素较强的菌体高产菌株含TTC的培养基属于填“选择”或“鉴别”培养基．对照组需涂布等量的以判断培养基是否被污染．挑取单菌落时若菌落周围则菌株合成胡萝卜素的能力较强． 3为了验证萃取物是否是胡萝卜素该同学将叶绿素b叶绿素a叶黄素萃取物和色素混合液含叶绿素b叶绿素a叶黄素和胡萝卜素依次点样在滤纸的12345位置如图甲所示并进行分离滤纸条上各色素带的位置为填字母时即可说明该萃取物最可能是胡萝卜素．
假如你班将举行一次英语班会主题为Howtobehealthy请你根据下面提示用英语写一篇发言稿. 注意1.字数120左右开头已给出不计入总词汇可适当发挥. 2.生词零食non﹣staplefood卫生hygiene Dearfriends.
OnlywhenyouhavefinishedyourhomeworkwatchTV. A.canyou B.youcan C.youhave D.haveyou
It'sasituationyouneverwanttofindyourselfin.Youareonvacationpeacefullyenjoyingtheplanet'snaturalwonders.Then﹣﹣﹣outofnowhere﹣﹣﹣awildcreatureattacks.Inordertohelpyouwe'vecomeupwithalistoftipsforsurvivingvariousanimalencounters. Bears Bearsbehaveaggressivelywhentheyaresurprised.Yourguideswilltellyoutowearabellinordertoscareawayanybearsthatmaybenearby.Donotgonearbearcubsastheirmotherswillattackviolentlyinordertoprotectthem.Playdeadifthebearattacks. Snakes Snakeskilltheirprey猎物byslowlysqueezinguntilitcannolongerbreathe.Shouldyoufindyourselfbeingtakeninbyasnakeyouareadvisedtoremainstillasstrugglingwillpromptthesnaketosqueeze.Useonearmasprotectionforyourribsanduseyourotherarmtounwindthesnake. Sharks Avoidlyingonthewater'ssurfaceinanareaknowntobepopulatedwithsharks.Yourfiguremaylooklikeasealoranotheranimalthatiscommonpreyforsharks.Theycanfeelvibrations振动fromhundredsofmetersawaysoswimmingislikelytodrawsharkstowardsyou.Makeslowmovementsandtrytogettoshore.Fightbackifyouareattackedbyashark.Targetitseyes. Wilddogs Occasionallywilddogscanbemoreofathreatthanmostpeoplethink.Aswithbigcatsfrighteningthedogwithloudsoundsandmakingyouappearlargercanpreventapossibleattack.Ifanattackdoesoccurremainstandingandtrykickingthedogintheface. 68.Whichofthefollowingisthebesttitleofthetext? A.Dosanddon'tswhenyouareindanger. B.Sometipsforsurvivinganimalencounters. C.Howtopreventananimalattack. D.Howtohaveagoodvacation. 69.Thetextiswrittenfor. A.touristsB.swimmers.C.guidesD.drivers 70.Theunderlinedwordcubsinparagraph2refersto. A.adultbearsB.malebearsC.babybearsD.motherbears 71.Ifyouareattackedbyasharkyoushould. A.playdeadbylyingstillB.hititseyes C.kickitsnoseD.yellforhelp.
下列与细胞相关的叙述正确的是
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