首页
试卷库
试题库
当前位置：
X题卡
>
所有题目
>
题目详情
假设检验的基本思想可以用______来解释。
查看本题答案
包含此试题的试卷
邮件分拣员考试《单项选择》真题及答案
点击查看
你可能感兴趣的试题
假设检验是用来判断样本与样本样本与总体的差异是由抽样误差引起还是本质差别造成的统计推断方法其基本思想
点值估计
区间估计
小概率反证法
参数估计
假设检验的基本思想是反证法思想
大概率
平均率
小概率
差别率
假设检验的基本思想是反证法思想
小概率
大概率
平均率
差别率
假设检验的基本思想可以用来解释
中心极限定理
置信区别
小概率事件
正态分布的性质
[中国建设银行]假设检验的基本思想可以用来解释
中心极限定理
置信区别
小概率事件
正态分布的性质
假设检验的基本思想可以用来解释
中心极限定理
置信区间
小概率事件原理
正态分布的性质
热门试题
更多
从所给的四个选项中选择最合适的一个填入问号处使之呈现一定的规律性
违法对于相当于对于假想
国际贸易是跨国界的交易活动是一个国家同世界其他国家或地区间的商品技术劳务和信息等的流通活动根据定义下列属于国际贸易的是
对于洪水相当于工业对于
国际法的识别是指在适用冲突规范时依照某一法律制度对有关事实或问题进行分类和定性将其归人一定法律范畴并对有关冲突规范进行解释的过程下列不属于国际法的识别的是
正圆柱体的高为10cm底面半径为cm那么在圆柱体的表面从A点到D点的最短距离为
某些媒分子通过使环绕肺气管的骨肉细胞收缩来抵御有毒气体对肺部的损害这使得肺部部分封闭起来当这些媒分子被不必要的激活时对某些无害的像花粉或家庭粉尘做出反应就出现了哮喘病有一项计划是开发一种药物通过阻碍接受由上文所说的媒分子发出的信息来防止哮喘病的发生以下哪一项如果是正确的将指出这项计划的最严重的缺陷
Ifthesalinityofoceanwaterisanalyzeditisfoundtovaryonlyslightlyfromplacetoplace.Neverthelesssomeofthesesmallchangesareimportant.Therearethreebasicprocessesthatcauseachangeinoceanicsalinity.Oneoftheseisthesubtractionofwaterfromtheoceanbymeansofevaporation—conversionofliquidwatertowatervapor.Inthismannerthesalinityisincreasedsincethesaltsstaybehind.Ifthisiscarriedtotheextremeofcoursewhitecrystalsofsaltwouldbeleftbehind;thisbythewayishowmuchofthetablesaltweuseisactuallyobtained. Theoppositeofevaporationisprecipitationsuchasrainbywhichwaterisaddedtotheocean.Heretheoceanisbeingdilutedsothatthesalinityisdecreased.Thismayoccurinareasofhighrainfallorincoastalregionswhereriversflowintotheocean.Thussalinitymaybeincreasedbythesubtractionofwaterbyevaporationordecreasedbytheadditionoffreshwaterbyprecipitationorrunoff. Normallyintropicalregionswherethesunisverystrongtheoceansalinityissomewhathigherthanitisinotherpartsoftheworldwherethereisnotasmuchevaporation.Similarlyincoastalregionswhereriversdilutetheseasalinityissomewhatlowerthaninotheroceanicareas. Athirdprocessbywhichsalinitymaybealteredisassociatedwiththeformationandmeltingofseaice.Whenseawaterisfrozenthedissolvedmaterialsareleftbehind.Inthismannerseawaterdirectlybeneathfreshlyformedseaicehasahighersalinitythanitdidbeforetheiceappeared.Ofcoursewhenthisicemeltsitwelltendtodecreasethesalinityofthesurroundingwater. IntheWeddellSeaoffAntarcticathedensestwaterintheoceansisformedasaresultofthisfreezingprocesswhichincreasesthesalinityofcoldwater.Thisheavywatersinksandisfoundinthedeeperportionsofoceansoftheworld. Accordingtotheauthortheoceanicsalinityisusuallylowerin
2011年我国全年货物进出口总额36421亿美元比上年增长22.5%其中出口18986亿美元增加20.3%进口17435亿美元增长24.9%进出口差额出口值与进口值差额的绝对值1551亿美元比上年减少265亿美元 2007—2011年我国全年货物出口额与上一年相比增长超过30%的年份有.
Prolonginghumanlifehasincreasedthesizeofthehumanpopulation.Manypeoplealivetodaywouldhavediedofchildhooddiseasesiftheyhadbeenbornahundredyearsago.Becausemorepeoplelivelongertherearemorepeoplearoundatanygiventime.Infactitisadecreaseindeathratesnotanincreaseinbirthratesthathasledtothepopulationexplosion. Prolonginghumanlifehasalsoincreasedthedependencyload.Inallsocietiespeoplewhoaredisabledortooyoungortoooldtoworkaredependentontherestofsocietytoprovideforthem.Inhuntingandgatheringculturesoldpeoplewhocouldnotkeepupmightbeleftbehindtodie.Intimesoffamineinfantsmightbeallowedtodiebecausetheycouldnotsurviveiftheirparentsstarvedwhereasiftheparentssurvivedtheycouldhaveanotherchild.Inmostcontemporary当代的societiespeoplefeelamoralobligationtokeeppeoplealivewhethertheycanworkornot.Wehaveagreatmanypeopletodaywholivepasttheageatwhichtheywanttoworkorareabletowork;wealsohaveruleswhichrequirepeopletoretireatacertainage.Unlessthesepeoplewereabletosavemoneyfortheirretirementsomebodyelsemustsupportthem.IntheUnitedStatesmanyretiredpeopleliveonsocialsecuritycheckswhicharesolittlethattheymustliveinnearpoverty.Olderpeoplehavemoreillnessthanyoungormiddle-agedpeople;unlesstheyhavewealthorprivateorgovernmentinsurancetheymustoftengoonwelfareiftheyhaveaseriousillness. Whenolderpeoplebecomesenileortooweaktocareforthemselvestheycreategraveproblemsfortheirfamilies.Inthepastandinsometraditionalculturestheywouldbecaredforathomeuntiltheydied.Todaywithmostmembersofahouseholdworkingorinschoolthereisoftennooneathomewhocancareforasickorweakperson.Tomeetthisneedagreatmanynursinghomesandconvalescent康复的hospitalshavebeenbuilt.Theseareoftenprofit-makingorganizationsalthoughsomearesponsored赞助byreligiousandothernonprofitgroups.Whileafewoftheseinstitutionsaregoodmostofthemaresimplydumpinggroundsforthedyinginwhichcareisgivenbypoorlypaidoverworkedandunder-skilledpersonnel. Itcanbelearnedfromthepassagethatinsometraditionalsocieties
人们缩减石油用量的一个办法是改用其他类型的燃料由于木材是可再生的资源且可保持持续供应家庭取暖用木头代替石油将是一个能确保将来有足够能源供应的办法如果下列哪项正确将最严重地削弱以上论述
有一些经济学家认为加速城市化以城市化为杠杆撬动内需增长不失为一个应对金融危机的积极选择并提出可以借鉴破窗理论当一扇窗户被打破以后主人自然要购置新玻璃这就是间接促进了玻璃厂的扩大再生产从而拉动了经济发展因此说城市化是加速经济发展的一项积极举措以下哪项如果为真最能质疑上述理论和观点
近年来浙江省商品交易市场呈现稳步发展态势2009年浙江省共有亿元以上商品交易市场670家比上年增加31家营业面积2298万平方米出租摊位39万个实现成交额9647亿元比上年增长7.8%从市场成交额看成交额达10亿元以上的商品交易市场189家占全部市场个数的28.2%实现成交额8139亿元其中10亿～50亿元的商品交易市场有156家50亿～100亿元的商品交易市场有17家100亿元以上的商品交易市场有16家从商品分类销售看一是与城乡居民生活息息相关的商品销售稳定增长其成交额最大所占比例最高食品饮料烟酒类成交额2127亿元比上年增长10.1%服装鞋帽类商品销售比重居第二位成交额2077亿元比上年增长9.2%二是随着居民消费水平提高和消费需求的多元化个人享受发展及服务性消费所带动的商品成交活跃文化办公用品类商品成交额135亿元同比增长20.1%体育娱乐用品类商品成交额18亿元同比增长25.6%家用电器和音像器材类商品成交额52亿元同比增长36%儿童玩具类商品成交额31亿元同比增长15.9%三是汽车销售保持快速增长所占比重有所上升汽车类实现成交额606亿元同比增长29.9%比上年提高1.1个百分点2008年浙江省平均每家亿元以上商品交易市场的成交额是______
Prolonginghumanlifehasincreasedthesizeofthehumanpopulation.Manypeoplealivetodaywouldhavediedofchildhooddiseasesiftheyhadbeenbornahundredyearsago.Becausemorepeoplelivelongertherearemorepeoplearoundatanygiventime.Infactitisadecreaseindeathratesnotanincreaseinbirthratesthathasledtothepopulationexplosion. Prolonginghumanlifehasalsoincreasedthedependencyload.Inallsocietiespeoplewhoaredisabledortooyoungortoooldtoworkaredependentontherestofsocietytoprovideforthem.Inhuntingandgatheringculturesoldpeoplewhocouldnotkeepupmightbeleftbehindtodie.Intimesoffamineinfantsmightbeallowedtodiebecausetheycouldnotsurviveiftheirparentsstarvedwhereasiftheparentssurvivedtheycouldhaveanotherchild.Inmostcontemporary当代的societiespeoplefeelamoralobligationtokeeppeoplealivewhethertheycanworkornot.Wehaveagreatmanypeopletodaywholivepasttheageatwhichtheywanttoworkorareabletowork;wealsohaveruleswhichrequirepeopletoretireatacertainage.Unlessthesepeoplewereabletosavemoneyfortheirretirementsomebodyelsemustsupportthem.IntheUnitedStatesmanyretiredpeopleliveonsocialsecuritycheckswhicharesolittlethattheymustliveinnearpoverty.Olderpeoplehavemoreillnessthanyoungormiddle-agedpeople;unlesstheyhavewealthorprivateorgovernmentinsurancetheymustoftengoonwelfareiftheyhaveaseriousillness. Whenolderpeoplebecomesenileortooweaktocareforthemselvestheycreategraveproblemsfortheirfamilies.Inthepastandinsometraditionalculturestheywouldbecaredforathomeuntiltheydied.Todaywithmostmembersofahouseholdworkingorinschoolthereisoftennooneathomewhocancareforasickorweakperson.Tomeetthisneedagreatmanynursinghomesandconvalescent康复的hospitalshavebeenbuilt.Theseareoftenprofit-makingorganizationsalthoughsomearesponsored赞助byreligiousandothernonprofitgroups.Whileafewoftheseinstitutionsaregoodmostofthemaresimplydumpinggroundsforthedyinginwhichcareisgivenbypoorlypaidoverworkedandunder-skilledpersonnel. Whatistheauthor’sattitudetowardthenursinghomesandconvalescenthospitalsmentionedintheparagraph
Morethanacenturyagotherelationshipbetweenglacialiceandtheamountofwaterintheoceanbasinswasfirstseen.Whenthegreaticesheetcoveredvastlandareasthesealevelwasloweredbecausethenormalreturnofwaterfromlandtotheoceanwasreduced.AsaresultthesealevelroseasIceAgeglaciersmeltedallowingthemeltedwaterstoflowintotheocean.Ifalltheglacialiceonthesurfaceoftheearthtodayshouldmeltthesealevelmightrisebymorethan150feet.Shorelinevariationsarealsoproducedthroughelevationordepressionoftheland.Duringtimesofglacierformationsthegreatweightoftheiceslowlydepressedtheearth’scrust.Removaloftheweightthroughglaciermeltingallowedtheslowreturnofthecrusttoitsformerposition.ChangesintheGreatIceclimatesfromcoolandwettowarmanddryproducedclimatechangesfarfromtheglaciatedarea.Forexampleattimesofcool-wetglacialclimateslevelsofinlandlakesroseincontrasttothedepressionofsealevel.Duringthewarm-dryinterglacialclimateslakelevelswerelowered.TheancientlakeBonnevillelargestoftheglaciallakesinWesternUnitedStatesoncecoveredmorethan20000squaremiles.Ithadamaximumdepthofmorethan1000feet.GreatSaltLakeinUtahistheshrunkenremnantofthisoncelargelake. AlthoughthefirsttimethatearlymanwalkedontheearthisuncertainheislargelyaproductoftheGreatIceAge.Presentinformationshowsthatduringthistimeheevolvedrapidlybothphysicallyandculturally.HismostprimitivetoolsandskeletalremainshavebeenfoundinsomeoftheoldestdepositscontemporarywiththeGreatIceAgeinAfricaAsiaandEurope.Theseareoftenassociatedwithremainsofextinctanimals.WiththedisappearanceofthegreaticesheetstheBronzeandIronAgeculturesevolved.Aboutthistimemanyanimalssuitedtocoolerclimatesdied. AlthoughmuchremainstobelearnedthestoryoftheGreatIceAgeisbeingunfoldedthroughtheeffortsofspecialistsinmanyfields.RecordingfieldobservationnewtheoriesandmethodsandworldwidestudiesofexistingglaciersarebringingaclearerunderstandingoftheGreatIceAge. WhydoestheauthorcitetheexampleoftheGreatSaltLakeinUtah
美国2006年人口普查显示男婴与女婴的比例是51:49等到这些孩子长到18岁时性别比例却发生了相反的变化男女比例是49:51而在25岁到34岁的单身族中性别比例严重失调男女比例是46:54美国越来越多的女性将面临找对象的压力如果以下陈述为真哪一项最有助于解释上述性别比例的变化
AlthoughwealreadyknowagreatdealaboutinfluenzaandalthoughtheWorldHealthOrganizationisconstantlycollectingdetailedinformationfromitschainofinfluenzareferencelaboratoriesthroughouttheworlditisextremelydifficultforepidemiologists流行病专家whostudyinfectiousdiseasetopredictwhenandwherethenextfluepidemicwilloccurandhowsevereitwillbe. TherearethreekindsofinfluenzavirusknownasABandC.InfluenzaCvirusisrelativelystableandcausesmildinfectionsthatdonotspreadfarthroughthepopulation.TheAandBtypesareunstableandareresponsiblefortheepidemicsthatcausefrequentconcern.Followinganyvirusattackthehumanbodybuildsupantibodieswhichconferimmunitytothatstrainofvirusbutaviruswiththecapacitytochangeitscharacterisabletoby-passthisprotection.VariabilityislessdevelopedintheinfluenzaBviruswhichaffectsonlyhumanbeings.AninfluenzaBvirusmaycauseawidespreadepidemicbutwillhavelittleeffectifintroducedintothesamecommunitysoonafterwardssincenearlyeveryonewillhavebuiltupantibodiesandwillbeimmune.TheinfluenzaAviruswhichaffectsanimalsalsoisextremelyunstableandisresponsibleforsomeoftheworstoutbreaksofthediseasesuchastheunparalleledpandemicorworldepidemicof1918-1919whenabouthalftheworld’spopulationwereinfectedandabouttwentymillionpeoplediedsomefrompneumoniacausedbythevirusitselfandsomefromsecondarycomplications并发症causedbybacteria. Accuratepredictionisdifficultbecauseofthecomplicationofthefactors.Aparticularvirusmayberelatedtoonetowhichsomeofthepopulationhavepartialinvolvedimmunity.Theextenttowhichitwillspreadwilldependonfactorssuchasitsownstrengthorvirulencetheeasewithwhichitcanbetransmittedandthestrengthoftheoppositionitencounters.Scientistshoweverhaveareliablegeneralpictureoftheworldsituation.InfluenzaAattacksusinwaveseverytwoorthreeyearswhileinfluenzaBwhichtravelsmoreslowlylaunchesitsmainassaultseverythreetosixyears.Theoutbreaksvaryfromisolatedcasestoepidemicsinvolvingatenthormoreofthepopulation.Wemayconfidentlyprophesythatsoonerorlaterlargenumbersofpeoplewillbefeelingtheunpleasanteffectsofsomekindofinfluenzavirus. WhichofthefollowingisNOTmentionedasafactorcontributingtotheextenttowhichavirusspreads
储蓄国债股票
请从以下四个图形中选出与其他三个不同的选项
2011年我国全年货物进出口总额36421亿美元比上年增长22.5%其中出口18986亿美元增加20.3%进口17435亿美元增长24.9%进出口差额出口值与进口值差额的绝对值1551亿美元比上年减少265亿美元 表中所列举的国家和地区中2011年与我国货物进出口贸易差额最大的是.
Morethanacenturyagotherelationshipbetweenglacialiceandtheamountofwaterintheoceanbasinswasfirstseen.Whenthegreaticesheetcoveredvastlandareasthesealevelwasloweredbecausethenormalreturnofwaterfromlandtotheoceanwasreduced.AsaresultthesealevelroseasIceAgeglaciersmeltedallowingthemeltedwaterstoflowintotheocean.Ifalltheglacialiceonthesurfaceoftheearthtodayshouldmeltthesealevelmightrisebymorethan150feet.Shorelinevariationsarealsoproducedthroughelevationordepressionoftheland.Duringtimesofglacierformationsthegreatweightoftheiceslowlydepressedtheearth’scrust.Removaloftheweightthroughglaciermeltingallowedtheslowreturnofthecrusttoitsformerposition.ChangesintheGreatIceclimatesfromcoolandwettowarmanddryproducedclimatechangesfarfromtheglaciatedarea.Forexampleattimesofcool-wetglacialclimateslevelsofinlandlakesroseincontrasttothedepressionofsealevel.Duringthewarm-dryinterglacialclimateslakelevelswerelowered.TheancientlakeBonnevillelargestoftheglaciallakesinWesternUnitedStatesoncecoveredmorethan20000squaremiles.Ithadamaximumdepthofmorethan1000feet.GreatSaltLakeinUtahistheshrunkenremnantofthisoncelargelake. AlthoughthefirsttimethatearlymanwalkedontheearthisuncertainheislargelyaproductoftheGreatIceAge.Presentinformationshowsthatduringthistimeheevolvedrapidlybothphysicallyandculturally.HismostprimitivetoolsandskeletalremainshavebeenfoundinsomeoftheoldestdepositscontemporarywiththeGreatIceAgeinAfricaAsiaandEurope.Theseareoftenassociatedwithremainsofextinctanimals.WiththedisappearanceofthegreaticesheetstheBronzeandIronAgeculturesevolved.Aboutthistimemanyanimalssuitedtocoolerclimatesdied. AlthoughmuchremainstobelearnedthestoryoftheGreatIceAgeisbeingunfoldedthroughtheeffortsofspecialistsinmanyfields.RecordingfieldobservationnewtheoriesandmethodsandworldwidestudiesofexistingglaciersarebringingaclearerunderstandingoftheGreatIceAge. ThebestsourceofinformationabouttheGreatIceAgeisobtainedfrom
从所给的四个选项中选择最合适的一个填入问号处使之呈现一定的规律性
AlthoughwealreadyknowagreatdealaboutinfluenzaandalthoughtheWorldHealthOrganizationisconstantlycollectingdetailedinformationfromitschainofinfluenzareferencelaboratoriesthroughouttheworlditisextremelydifficultforepidemiologists流行病专家whostudyinfectiousdiseasetopredictwhenandwherethenextfluepidemicwilloccurandhowsevereitwillbe. TherearethreekindsofinfluenzavirusknownasABandC.InfluenzaCvirusisrelativelystableandcausesmildinfectionsthatdonotspreadfarthroughthepopulation.TheAandBtypesareunstableandareresponsiblefortheepidemicsthatcausefrequentconcern.Followinganyvirusattackthehumanbodybuildsupantibodieswhichconferimmunitytothatstrainofvirusbutaviruswiththecapacitytochangeitscharacterisabletoby-passthisprotection.VariabilityislessdevelopedintheinfluenzaBviruswhichaffectsonlyhumanbeings.AninfluenzaBvirusmaycauseawidespreadepidemicbutwillhavelittleeffectifintroducedintothesamecommunitysoonafterwardssincenearlyeveryonewillhavebuiltupantibodiesandwillbeimmune.TheinfluenzaAviruswhichaffectsanimalsalsoisextremelyunstableandisresponsibleforsomeoftheworstoutbreaksofthediseasesuchastheunparalleledpandemicorworldepidemicof1918-1919whenabouthalftheworld’spopulationwereinfectedandabouttwentymillionpeoplediedsomefrompneumoniacausedbythevirusitselfandsomefromsecondarycomplications并发症causedbybacteria. Accuratepredictionisdifficultbecauseofthecomplicationofthefactors.Aparticularvirusmayberelatedtoonetowhichsomeofthepopulationhavepartialinvolvedimmunity.Theextenttowhichitwillspreadwilldependonfactorssuchasitsownstrengthorvirulencetheeasewithwhichitcanbetransmittedandthestrengthoftheoppositionitencounters.Scientistshoweverhaveareliablegeneralpictureoftheworldsituation.InfluenzaAattacksusinwaveseverytwoorthreeyearswhileinfluenzaBwhichtravelsmoreslowlylaunchesitsmainassaultseverythreetosixyears.Theoutbreaksvaryfromisolatedcasestoepidemicsinvolvingatenthormoreofthepopulation.Wemayconfidentlyprophesythatsoonerorlaterlargenumbersofpeoplewillbefeelingtheunpleasanteffectsofsomekindofinfluenzavirus. AccordingtotheauthorwhichofthefollowingisNOTtrueaboutinfluenza
Morethanacenturyagotherelationshipbetweenglacialiceandtheamountofwaterintheoceanbasinswasfirstseen.Whenthegreaticesheetcoveredvastlandareasthesealevelwasloweredbecausethenormalreturnofwaterfromlandtotheoceanwasreduced.AsaresultthesealevelroseasIceAgeglaciersmeltedallowingthemeltedwaterstoflowintotheocean.Ifalltheglacialiceonthesurfaceoftheearthtodayshouldmeltthesealevelmightrisebymorethan150feet.Shorelinevariationsarealsoproducedthroughelevationordepressionoftheland.Duringtimesofglacierformationsthegreatweightoftheiceslowlydepressedtheearth’scrust.Removaloftheweightthroughglaciermeltingallowedtheslowreturnofthecrusttoitsformerposition.ChangesintheGreatIceclimatesfromcoolandwettowarmanddryproducedclimatechangesfarfromtheglaciatedarea.Forexampleattimesofcool-wetglacialclimateslevelsofinlandlakesroseincontrasttothedepressionofsealevel.Duringthewarm-dryinterglacialclimateslakelevelswerelowered.TheancientlakeBonnevillelargestoftheglaciallakesinWesternUnitedStatesoncecoveredmorethan20000squaremiles.Ithadamaximumdepthofmorethan1000feet.GreatSaltLakeinUtahistheshrunkenremnantofthisoncelargelake. AlthoughthefirsttimethatearlymanwalkedontheearthisuncertainheislargelyaproductoftheGreatIceAge.Presentinformationshowsthatduringthistimeheevolvedrapidlybothphysicallyandculturally.HismostprimitivetoolsandskeletalremainshavebeenfoundinsomeoftheoldestdepositscontemporarywiththeGreatIceAgeinAfricaAsiaandEurope.Theseareoftenassociatedwithremainsofextinctanimals.WiththedisappearanceofthegreaticesheetstheBronzeandIronAgeculturesevolved.Aboutthistimemanyanimalssuitedtocoolerclimatesdied. AlthoughmuchremainstobelearnedthestoryoftheGreatIceAgeisbeingunfoldedthroughtheeffortsofspecialistsinmanyfields.RecordingfieldobservationnewtheoriesandmethodsandworldwidestudiesofexistingglaciersarebringingaclearerunderstandingoftheGreatIceAge. WhichofthefollowingisNOTimpliedinthepassage
Ifthesalinityofoceanwaterisanalyzeditisfoundtovaryonlyslightlyfromplacetoplace.Neverthelesssomeofthesesmallchangesareimportant.Therearethreebasicprocessesthatcauseachangeinoceanicsalinity.Oneoftheseisthesubtractionofwaterfromtheoceanbymeansofevaporation—conversionofliquidwatertowatervapor.Inthismannerthesalinityisincreasedsincethesaltsstaybehind.Ifthisiscarriedtotheextremeofcoursewhitecrystalsofsaltwouldbeleftbehind;thisbythewayishowmuchofthetablesaltweuseisactuallyobtained. Theoppositeofevaporationisprecipitationsuchasrainbywhichwaterisaddedtotheocean.Heretheoceanisbeingdilutedsothatthesalinityisdecreased.Thismayoccurinareasofhighrainfallorincoastalregionswhereriversflowintotheocean.Thussalinitymaybeincreasedbythesubtractionofwaterbyevaporationordecreasedbytheadditionoffreshwaterbyprecipitationorrunoff. Normallyintropicalregionswherethesunisverystrongtheoceansalinityissomewhathigherthanitisinotherpartsoftheworldwherethereisnotasmuchevaporation.Similarlyincoastalregionswhereriversdilutetheseasalinityissomewhatlowerthaninotheroceanicareas. Athirdprocessbywhichsalinitymaybealteredisassociatedwiththeformationandmeltingofseaice.Whenseawaterisfrozenthedissolvedmaterialsareleftbehind.Inthismannerseawaterdirectlybeneathfreshlyformedseaicehasahighersalinitythanitdidbeforetheiceappeared.Ofcoursewhenthisicemeltsitwelltendtodecreasethesalinityofthesurroundingwater. IntheWeddellSeaoffAntarcticathedensestwaterintheoceansisformedasaresultofthisfreezingprocesswhichincreasesthesalinityofcoldwater.Thisheavywatersinksandisfoundinthedeeperportionsofoceansoftheworld. Whatdoesthewordsubtractioninthefourthlineofthefirstparagraphmean
AlthoughwealreadyknowagreatdealaboutinfluenzaandalthoughtheWorldHealthOrganizationisconstantlycollectingdetailedinformationfromitschainofinfluenzareferencelaboratoriesthroughouttheworlditisextremelydifficultforepidemiologists流行病专家whostudyinfectiousdiseasetopredictwhenandwherethenextfluepidemicwilloccurandhowsevereitwillbe. TherearethreekindsofinfluenzavirusknownasABandC.InfluenzaCvirusisrelativelystableandcausesmildinfectionsthatdonotspreadfarthroughthepopulation.TheAandBtypesareunstableandareresponsiblefortheepidemicsthatcausefrequentconcern.Followinganyvirusattackthehumanbodybuildsupantibodieswhichconferimmunitytothatstrainofvirusbutaviruswiththecapacitytochangeitscharacterisabletoby-passthisprotection.VariabilityislessdevelopedintheinfluenzaBviruswhichaffectsonlyhumanbeings.AninfluenzaBvirusmaycauseawidespreadepidemicbutwillhavelittleeffectifintroducedintothesamecommunitysoonafterwardssincenearlyeveryonewillhavebuiltupantibodiesandwillbeimmune.TheinfluenzaAviruswhichaffectsanimalsalsoisextremelyunstableandisresponsibleforsomeoftheworstoutbreaksofthediseasesuchastheunparalleledpandemicorworldepidemicof1918-1919whenabouthalftheworld’spopulationwereinfectedandabouttwentymillionpeoplediedsomefrompneumoniacausedbythevirusitselfandsomefromsecondarycomplications并发症causedbybacteria. Accuratepredictionisdifficultbecauseofthecomplicationofthefactors.Aparticularvirusmayberelatedtoonetowhichsomeofthepopulationhavepartialinvolvedimmunity.Theextenttowhichitwillspreadwilldependonfactorssuchasitsownstrengthorvirulencetheeasewithwhichitcanbetransmittedandthestrengthoftheoppositionitencounters.Scientistshoweverhaveareliablegeneralpictureoftheworldsituation.InfluenzaAattacksusinwaveseverytwoorthreeyearswhileinfluenzaBwhichtravelsmoreslowlylaunchesitsmainassaultseverythreetosixyears.Theoutbreaksvaryfromisolatedcasestoepidemicsinvolvingatenthormoreofthepopulation.Wemayconfidentlyprophesythatsoonerorlaterlargenumbersofpeoplewillbefeelingtheunpleasanteffectsofsomekindofinfluenzavirus. Whichofthefollowingisthemostdangerousvirusaccordingtothepassage
近年来浙江省商品交易市场呈现稳步发展态势2009年浙江省共有亿元以上商品交易市场670家比上年增加31家营业面积2298万平方米出租摊位39万个实现成交额9647亿元比上年增长7.8%从市场成交额看成交额达10亿元以上的商品交易市场189家占全部市场个数的28.2%实现成交额8139亿元其中10亿～50亿元的商品交易市场有156家50亿～100亿元的商品交易市场有17家100亿元以上的商品交易市场有16家从商品分类销售看一是与城乡居民生活息息相关的商品销售稳定增长其成交额最大所占比例最高食品饮料烟酒类成交额2127亿元比上年增长10.1%服装鞋帽类商品销售比重居第二位成交额2077亿元比上年增长9.2%二是随着居民消费水平提高和消费需求的多元化个人享受发展及服务性消费所带动的商品成交活跃文化办公用品类商品成交额135亿元同比增长20.1%体育娱乐用品类商品成交额18亿元同比增长25.6%家用电器和音像器材类商品成交额52亿元同比增长36%儿童玩具类商品成交额31亿元同比增长15.9%三是汽车销售保持快速增长所占比重有所上升汽车类实现成交额606亿元同比增长29.9%比上年提高1.1个百分点2007年浙江省汽车类销售成交额约为______
大城市的公共运输当局正在同赤字作斗争乘客抱怨延误和故障增多服务有所减少以及车费的增加因为所有这些原因以及因为汽油价格并不是高不可攀使得使用公共交通乘客的数目已经下降增加了赤字下列哪项被上述陈述所支持
近年来浙江省商品交易市场呈现稳步发展态势2009年浙江省共有亿元以上商品交易市场670家比上年增加31家营业面积2298万平方米出租摊位39万个实现成交额9647亿元比上年增长7.8%从市场成交额看成交额达10亿元以上的商品交易市场189家占全部市场个数的28.2%实现成交额8139亿元其中10亿～50亿元的商品交易市场有156家50亿～100亿元的商品交易市场有17家100亿元以上的商品交易市场有16家从商品分类销售看一是与城乡居民生活息息相关的商品销售稳定增长其成交额最大所占比例最高食品饮料烟酒类成交额2127亿元比上年增长10.1%服装鞋帽类商品销售比重居第二位成交额2077亿元比上年增长9.2%二是随着居民消费水平提高和消费需求的多元化个人享受发展及服务性消费所带动的商品成交活跃文化办公用品类商品成交额135亿元同比增长20.1%体育娱乐用品类商品成交额18亿元同比增长25.6%家用电器和音像器材类商品成交额52亿元同比增长36%儿童玩具类商品成交额31亿元同比增长15.9%三是汽车销售保持快速增长所占比重有所上升汽车类实现成交额606亿元同比增长29.9%比上年提高1.1个百分点根据材料下列结论中不能推出的是______
甲乙两人绕长为210千米的环形跑道同时同地同向行驶甲速度为160千米/小时乙速度为20千米/小时每当甲追上乙时甲的速度减少乙的速度增加问当两人速度相同时共行驶多少距离
热门题库
更多
邮政储汇业务员考试
邮政代理金融业务网点考试
邮件分拣员考试
机要业务员考试
邮件转运员考试
邮政业务档案员
邮政投递员考试
商业银行招聘考试
国家银行招聘考试
银行招聘考试(面试部分)
银行招聘考试(综合知识)
事业单位招聘考试
铁塔公司选聘考试
供电公司招聘考试
广播电视报社招聘
中国移动招聘考试
湘公网安备 43130202000226号