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射击比赛中，某队员10次射击成绩如图所示，则该队员的平均成绩是 环．
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在比赛中如果某队在场上准备比赛的队员少于名时该队由于缺少队员而告负
为了解射击运动员小杰的集训效果教练统计了他集训前后的两次测试成绩每次测试射击10次制作了如图所示的条
根据以往的成绩记录甲乙两名队员射击击中目标靶的环数的频率分布情况如图所示Ⅰ求上图中的值Ⅱ甲队员进行一
甲乙两名射击运动员中进行射击比赛两人在相同条件下各射击10次射击的成绩如图10所示.根据图中信息回答
受伤队员经同意离场护理后未经裁判员同意擅自进场参加比赛裁判员应该
暂停比赛，警告该队员，间接任意球恢复比赛。
比赛成死球后，警告该队员，间接任意球恢复比赛。
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某军训__到打靶场进行射击训练队员甲每次射击的命中率为50%队员乙每次射击的命中率为80%教练规定今
2次
1.25次
2.5次
1.5次
甲乙两人在一次射击比赛中各射靶5次两人成绩的条形统计图如图所示则
甲的成绩的平均数小于乙的成绩的平均数
甲的成绩的中位数等于乙的成绩的中位数
甲的成绩的方差小于乙的成绩的方差
甲的成绩的极差小于乙的成绩的极差
甲乙两人在一次射击比赛中各射靶5次两人成绩的条形统计图如图所示则
甲的成绩的平均数小于乙的成绩的平均数
甲的成绩的中位数等于乙的成绩的中位数
甲的成绩的方差小于乙的成绩的方差
甲的成绩的极差小于乙的成绩的极差
一组射击队员在一次射击训练中的射击成绩如下．单位环 请你对上面的射击成绩进行统计． 1这一
在篮球比赛中当某队请求替换时应由亲自到记录台提出
该队的教练员
该队准备替换上场的替补队员
其他替补队员
助理教练员或随队人员
甲乙两人进行射击比赛在相同条件下各射击10次他们的平均成绩均为8环10次射击成绩的方差分别是S2甲=
根据以往的成绩记录甲乙两名队员射击击中目标靶的环数的频率分布情况如图所示.假设每名队员每次射击相互独
贵州省第十届运动会将于2018年8月8日在遵义市奥体中心开幕某校有2名射击队员在比赛中的平均成绩均为
方差
中位数
众数
最高环数
当某队员第二次被判粗鲁行为犯规时则应
该队失一分并由对方发球
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某军训__到打靶场进行射击训练队员甲每次射击的命中率为50%队员乙每次射击的命中率为80%教练规定今
2次
1.25次
2.5次
1.5次
军训时甲乙两名同学进行射击比赛共比赛10场每场比赛各射击四次且用每场击中环数之和作为该场比赛的成绩
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当某队队员投篮的球离开该队员的手时该队的结束
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设NA为阿伏加德罗常数的数值下列说法不正确的是
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能正确表示下列反应的离子方程式为
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今年是门捷列夫发现元素周期律150周年联合国将2019年定为国际化学元素周期表年．下列有关化学元素周期表的说法正确的是
Itissimpleenoughtosaythatsincebookshaveclassesfictionbiographypoetry﹣weshouldseparatethemandtakefromeachwhatitisrightthateachshouldgiveus.Yetfewpeopleaskfrombookswhatbookscangiveus.Mostcommonlywecometobookswithblurredanddividedmindsaskingoffictionthatitshallbetrueofpoetrythatitshallbefalseofbiographythatitshallbeflatteringofhistorythatitshallenforceourownprejudices.Ifwecouldbanishallsuchpreconceptionwhenwereadthatwouldbeanadmirablebeginning.Donotdictatetoyourauthor;trytobecomehim.Behisfellowworkerandaccomplice.Ifyouhangbackandreserveandcriticizeatfirstyouarepreventingyourselffromgettingthefullestpossiblevaluefromwhatyouread.Butifyouopenyourmindaswidelyaspossiblethensignsandhintsofalmostimperceptiblefinessfromthetwistandturnofthefirstsentenceswillbringyouintothepresenceofahumanbeingunlikeanyother.Steepyourselfinthisacquaintyourselfwiththisandsoonyouwillfindthatyourauthorisgivingyouorattemptingtogiveyousomethingfarmoredefinite.Thethirtytwochaptersofanovel﹣ifweconsiderhowtoreadanovelfirst﹣areanattempttomakesomethingasformedandcontrolledasabuildingbutwordsaremoreimpalpablethanbricksreadingisalongerandmorecomplicatedprocessthanseeing.Perhapsthequickestwaytounderstandtheelementsofwhatanovelistisdoingisnottoreadbuttowrite;tomakeyourownexperimentwiththedangersanddifficultiesofwords.Recallthensomeeventthathasleftadistinctimpressiononyou﹣howatthecornerofthestreetperhapsyoupassedtwopeopletalking.Atreeshook;anelectriclightdanced;thetoneofthetalkwascomicbutalsotragic;awholevisionanentireconceptionseemedcontainedinthatmoment.1Whatdoestheauthormeanbysaying'Yetfewpeopleaskfrombookswhatbookscangiveus.'?A.Theauthormeansthatlotsofpeoplereadfewbooks.B.Theauthorthinksthatreadershaveonlyabsorbedpartofknowledgeinbooks.C.Theauthorholdsthatfewpeoplehaveaproperideaaboutwhatcontentsomekindofbooksshouldinclude.D.Theauthorconsidersthatreaderscanscarcelyunderstandmostofthebooks.2Accordingtothepassagewhichofthefollowingstatementisright?A.Areadershouldfindsomemistakeswhenheisreading.B.Themoredifficultabookisthemoreyoucangetfromit.C.Toreadsomethingiseasierthantowatchsomething.D.Oneshouldbeinthesametrackwiththewriterwhenheisreading.3Whatisthepossiblemeaningof'impalpable'Paragraph4inthepassage?A.Clear.B.Elusive.C.Delicate.D.Precise.4Whenawriteriswritingheoftengetthewholeconception.A.afteralongtime'sthinkingB.throughaninstantinspirationC.accordingtohisownexperienceD.bywayofwatchingtheobjectsattentively
Witnessingfriends'vacationslovelivesandworksuccessesonFacebookcancauseenvyandtrigger引发feelingsofmiseryandlonelinessaccordingtoGermanresearchers.AstudyconductedjointlybytwoGermanuniversitiesfoundstrongenvyonFacebooktheworld'slargestsocialnetworkthatnowhasoveronebillionusersandhasproducedaplatformforsocialcomparison.Theresearchersfoundthatoneinthreepeoplefeltworseaftervisitingthesiteandmoredissatisfiedwiththeirliveswhilepeoplewhobrowsedwithoutcontributingwereaffectedthemost.'WeweresurprisedbyhowmanypeoplehaveanegativeexperiencefromFacebookwithenvyleavingthemfeelinglonelyfrustratedorangry'researcherHannaKrasnovafromtheInstituteofInformationSystemsatBerlin'sHumboldtUniversitytoldthereporters.'FromourobservationssomeofthesepeoplewillthenleaveFacebookoratleastreducetheiruseofthesite'saidKrasnovaaddingtosuppositionthatFacebookcouldbereachingsaturationpoint饱和点insomemarkets.ResearchersfromHumboldtUniversityandfromDarmstadt'sTechnicalUniversityfoundvacationphotoswerethebiggestcauseofangerwithmorethanhalfofenvyincidentstriggeredbyholidaysnapsonFacebook.SocialinteractionwasthesecondmostcommoncauseofenvyasuserscouldcomparehowmanybirthdaygreetingstheyreceivedtothoseoftheirFacebookfriendsandhowmany'likes'orcommentsweremadeonphotosandpostings.'Passivefollowingtriggersinvidiousmotionswithusersmainlyenvyinghappinessofothersthewayothersspendtheirvacationsandsocialize'theresearcherssaidinthereport'EnvyonFacebook:AHiddenThreattoUsers'LifeSatisfaction?'releasedonTuesday.'ThespreadandcommonlyseenpresenceofenvyonSocialNetworkingSitesisshowntoundermineusers'lifesatisfaction.'Theyfoundpeopleagedintheirmid﹣30sweremostlikelytoenvyfamilyhappinesswhilewomenweremorelikelytoenvyphysicalattractiveness.Thesefeelingsofenvywerefoundtocausesomeuserstoboast夸大moreabouttheirachievementsonthesiterunbyFacebookInc.toportray描绘themselvesinabetterlight.Menwereshowntopostmoreself﹣promotionalcontentonFacebooktoletpeopleknowabouttheiraccomplishmentswhilewomenstressedtheirgoodlooksandsociallives.Theresearchersbasedtheirfindingsontwostudiesinvolving600peoplewiththeresultstobepresentedataconferenceoninformationsystemsinGermanyinFebruary.ThefirststudylookedatthescalescopeandnatureofenvyincidentstriggeredbyFacebookandthesecondathowenvywaslinkedtopassiveuseofFacebookandlifesatisfaction.TheresearcherssaidtheparticipantsinbothstudieswereGermanbuttheyexpectedthefindingstoholdinternationallyasenvyisauniversalfeelingandpossiblyimpactFacebookusage.'Fromaprovider'sperspectiveourfindingssignalthatusersfrequentlyperceiveFacebookastressfulenvironmentwhichmayinthelongrunendangerplatformsustainability'theresearchersconcluded.1Theunderlinedword'invidious'inParagraph4probablymeans''.A.powerfulB.differentC.unpleasantD.personal2WhichofthefollowingaboutFacebookenvyisNOTtrueaccordingtothepassage?A.Peopleintheir30susuallyenvyfamilyhappiness.B.Womenprobablyaremoreconcernedabouttheirlooks.C.Menwanttopostmoreabouttheiraccomplishments.D.Womendon'tfocusmuchattentiononsociallives.3AccordingtothesurveyFacebookenvymayresultin.A.morepeopleregisteringandbecomingmembersofthesiteB.themostprivatedetailsofindividualsbeinggivenawayC.usersspendingmoretimebrowsingothers'blogsD.usersshowingofftheirachievementsintentionally4Whichofthefollowingcouldserveasthebesttitleforthispassage?A.FacebookreflectswhatyourlifeislikeB.WhataffectsyourlifequalityonFacebookC.DiscontentcausedbyusingFacebookmaymakeyoumiserableD.Howtopreventsocialnetworkwebsitesaffectingyourlifemuch
Eyesightplaysaveryimportantroleinourdailylife.Everywakingmomenttheeyesareworkingtoseetheworldaroundus.OverfortypercentofAmericansworryaboutlosingeyesightbutit'seasytoincludestepsintoourdailylifetoensurehealthyeyes.Herearefivesuggestionsforalifetimeofhealthyeyesight:Scheduleyearlyexams.1Expertsadviseparentstobringbabies6to12monthsofagetothedoctorforacarefulcheck.Thegoodnewsisthatmillionsofchildrennowcanhaveyearlyeyeexamsandfollowingtreatmentincludingeye﹣glasses.ProtectagainstUVrays.Long﹣termstayinthesuncreatesrisktoyoureyes.Nomatterwhattheseasonisit'sextremelyimportanttowearsunglasses.2Giveyoureyesabreak.Two﹣thirdsofAmericansspenduptosevenhoursadayusingcomputersorotherdigitalproducts.3Expertsrecommendthatpeoplepracticethe20/20/20rule:every20minutestakea20﹣secondbreakandlookatsomething20feetaway.4Aspartofahealthydieteatmorefruitsandvegetableseachday.VitaminsCandEhelpprotecteyesightandpromoteeyehealth.Practicesafewearandcareofcontactlenses隐形眼镜.ManyAmericansusecontactlensestoimprovetheireyesight.Whilesomefollowthemedicalguidanceforwearingcontactlensesmanyarebreakingtherulesandputtingtheireyesightatrisk.5Otherwiseyoumayhaveproblemssuchasredeyespainintheeyesoramoreseriouscondition.A.Eatyourgreens.B.Eyecareshouldbeginearlyinlife.C.Theycanproperlyprotectyoureyes.D.Stayingoodshapebytakingmorevitamins.E.Parentsusuallydon'tcareabouttheirowneyesight.F.Alwaysfollowthedoctor'sadviceforappropriatewear.G.Thisfrequenteyeactivityincreasestheriskforeyetiredness.
自门捷列夫发现元素周期律以来人类对自然的认识程度逐步加深元素周期表中的成员数目不断增加．回答下列问题 12016年IUPAC确认了四种新元素其中一种为Mc中文名为“镁”．元素Mc可由反应端Am+Ca→288Mc+3n得到．该元素的质子数为287Mc与288Mc互为 2Mc位于元素周期表中第VA族同族元素N的一种氢化物为NH2NH2写出该化合物分子的电子式．该分子内存在的共价键类型有． 3该族中的另一元素P能呈现多种化合价其中+3价氧化物的分子式为+5价简单含氧酸的分子式为
奥沙拉秦是曾用于治疗急慢性溃疡性结肠炎的药物其由水杨酸为起始物的合成路线如图 回答下列问题 1X的结构简式为由水杨酸制备X的反应类型为． 2由X制备Y的反应试剂为． 3工业上常采用廉价的CO2与Z反应制备奥沙拉秦通入的CO2与Z的物质的量之比至少应为． 4奥沙拉秦的分子式为其核磁共振氢谱为组峰峰面积比为． 5若将奥沙拉秦用HCl酸化后分子中含氧官能团的名称为． 6W是水杨酸的同分异构体可以发生银镜反应W经碱催化水解后再酸化可以得到对苯二酚．W的结构简式为
根据图中的能量关系可求得C﹣H的键能为
下列实验现象与实验操作不相匹配的是
立德粉ZnS•BaSO4也称锌钡白是一种常用白色颜料．回答下列问题 1利用焰色反应的原理既可制作五彩缤纷的节日烟花亦可定性鉴别某些金属盐．灼烧立德粉样品时钡的焰色为填标号． A．黄色B．红色C．紫色D．绿色 2以重晶石BaSO4为原料可按如图工艺生产立德粉 ①在回转炉中重晶石被过量焦炭还原为可溶性硫化钡该过程的化学方程式为．回转炉尾气中含有有毒气体生产上可通过水蒸气变换反应将其转化为CO2和一种清洁能源气体该反应的化学方程式为． ②在潮湿空气中长期放置的“还原料”会逸出臭鸡蛋气味的气体且水溶性变差其原因是“还原料”表面生成了难溶于水的填化学式． ③沉淀器中反应的离子方程式为． 3成品中S2﹣的含量可以用“碘量法”测得．称取mg样品置于碘量瓶中移取25.00mL0.1000mol•L﹣1的I2﹣KI溶液于其中并加入乙酸溶液密闭置暗处反应5min有单质硫析出．以淀粉为指示剂过量的I2用0.1000mol•L﹣1Na2S2O3溶液滴定反应式为I2+2S2O32﹣═2I﹣+S4O62﹣．测定时消耗Na2S2O3溶液体积VmL．终点颜色变化为样品中S2﹣的含量为写出表达式．
环氧树脂因其具有良好的机械性能绝缘性能以及与各种材料的粘结性能已广泛应用于涂料和胶黏剂等领域．下面是制备一种新型环氧树脂G的合成路线已知以下信息①②③回答下列问题1A是一种烯烃化学名称为C中官能团的名称为．2由B生成C的反应类型为．3由C生成D的反应方程式为．4E的结构简式为．5E的二氯代物有多种同分异构体请写出其中能同时满足以下条件的芳香化合物的结构简式．①能发生银镜反应②核磁共振氢谱有三组峰且峰面积比为321．6假设化合物DF和NaOH恰好完全反应生成1mol单一聚合度的G若生成的NaCl和H2O的总质量为765g则G的n值理论上应等于．
下列关于普伐他汀的水解产物结构简式如图的说法不正确的是
氧化亚氮N2O是一种强温室气体且易转换成颗粒污染物．研究氧化亚氮分解对环境保护有重要意义． 1污水生物脱氮过程中在异养微生物催化下硝酸铵可分解为N2O和另一种产物该反应的化学方程式为． 2已知反应2N2Og＝2N2g+O2g的△H＝﹣163kJ•mol﹣11molN2g1molO2g分子中化学键断裂时分别需要吸收945kJ498kJ的能量则1molN2Og分子中化学键断裂时需要吸收的能量为kJ． 3在一定温度下的恒容容器中反应2N2Og＝2N2g+O2g的部分实验数据如下 ①在0～20min时段反应速率vN2O为mol•L﹣1•min﹣1． ②若N2O起始浓度c0为0.150mol•L﹣1则反应至30min时N2O的转化率α＝．比较不同起始浓度时N2O的分解速率vc0＝0.150mol•L﹣1vc0＝0.100mol•L﹣1填“＞”“＝”或“＜”． ③不同温度T下N2O分解半衰期随起始压强的变化关系如图所示图中半衰期指任一浓度N2O消耗一半时所需的相应时间则T1T2填“＞”“＝”或“＜”．当温度为T1起始压强为p0反应至t1min时体系压强p＝用p0表示． 4碘蒸气存在能大幅度提高N2O的分解速率反应历程为 第一步I2g⇌2Ig快反应 第二步Ig+N2Og→N2g+IOg慢反应 第三步IOg+N2Og→N2g+O2g+Ig快反应 实验表明含碘时N2O分解速率方程v＝k•cN2O•[cI2]0.5k为速率常数．下列表述正确的是填标号． A．N2O分解反应中k含碘＞k无碘 B．第一步对总反应速率起决定作用 C．第二步活化能比第三步大 D．I2浓度与N2O分解速率无关
一定温度下AgCls⇌Ag+aq+Cr﹣aq体系中cAg+和cCl﹣的关系如图所示．下列说法正确的是
WhenIvolunteeredtospendasummeronaland﹣basedwhale﹣watchingprojectintheWestofScotlandtheprojectsecretarywarnedme'Youhavetobeabletodetectthewhalesfromtheshore﹣it'snotaseasyasyouthink.'AlthoughIassumedIwaswell﹣qualifiedforthejobatthestartoftheprojectIhadafewembarrassingmomentsscreaming'Whale!'beforerealizingthatwhatIwaspointingoutwereonlywavesbreakingoverunderwaterrocksnotseacreaturesatall.AfterawhileItrainedmyeyesto'see'﹣todistinguishbetweenwaveshittingrocksandtherollingmovementofwhalesunderwater.Ispentalotoftimejustwatchingtheseathroughmybinoculars双筒望眼镜lookingactivelyforanythingthatindicatedsealifebelow.Mybinocularsenabledmetospotthefins鳍ofadolphinagainstthedarknessoftheseaandwithoutagoodpairofbinocularsIdefinitelywouldhavemissedoutonlotsofamazingsealife.InadditionIeventuallyrealizedthatthebirdsprovideuswithsignalsthatwhalesanddolphinsmaybeinthearea.Wherethereisagroupoffeedingseabirdssuchasseagullsorgannetsthereisoftenawhalefeedingunderthem.Gannetsarereallyeasytospotfromadistance﹣theydropoutoftheskyatspeedsofupt0100kphspearingthesurfaceandsendingburstsofwaterupbehindthem.Ifyouwanttotrythisactivityitisworthorganizingandplanningcarefullyforwhalewatching.Irecommendhavinganotebookandpencilnearbytorecorddetailsofwhatyouveseenandtheenvironmentalconditionsatthetime.ThisisnotonlyahelpfulaidingeneralbutyoucanalsocontributeyoursightingstoresearchprojectssuchastheSeaWatchFoundationwhicharemonitoringthedistributionofwhalesanddolphins.DespitetheearlydisappointmentsIhadIthinkthereisundoubtedlysomethingveryspecialaboutwatchingwhales.Nothingcancomparewiththesecretthrillandthepeacefulnessofseeingawildanimaljustdoingitsownthing.1Whatdidtheauthorlearnfromtheembarrassingmoments?A.Itwashardtocarryouttheproject.B.Theprojectsecretarywasverystrict.C.Mostwhaleswerenotafraidofhumans.D.Whale﹣watchingwasnotaseasyasexpected.2WhichofthefollowingismentionedinParagraph2?A.Thefeaturesoftheauthor'sbinoculars.B.Binoculars'importanceforwhale﹣watching.C.Howtheauthorgotagoodpairofbinoculars.D.Howtousebinocularswhenwatchingwhales.3Theauthoradvisedwhalewatchersto.A.recordwhale﹣watchingdetailsB.becarefulwhenwatchingwhalesC.watchwhalesfromtheshoreonlyD.seekhelpfromtheSeaWatchFoundation4Whatwouldbethebesttitleforthetext?A.PleasantsummermemoriesB.ThethrillofwatchingwhalesC.Usefulwhale﹣watchingadviceD.Afantasticworldunderthewater
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