某图样采用1:2的比例绘制时，标注尺寸为（）。

2.下列关于“符号”说法错误的是（）

2.下列关于传播类型说法正确的有（）

已知H3PO4的pKa1=2.12,pKa2=7.20,pKa3=12.36。今有一磷酸盐溶液的pH=12.78,则其主要存在形式是()

已知H3PO4的pKa1=2.12,pKa2=7.20,pKa3=12.36。今有一磷酸盐溶液的pH=4.78,则其主要存在形式是()

表达“从一个关系的所有行中提取出满足某些条件的行”，“从一个关系的所有列中提取出某些列”“提取出属于一个关系但不属于另一关系的所有元组”“将两个关系必须按照某种条件串接成一个较大的关系”的操作依次是（）。1、并2、交3、积4、选择5、投影6、差7、连接

13.在服务器端运行环境的搭建中，Tomcat既可以作为JSP引擎，也可以作为Web服务器。（）

13．（）是一种可以在一个或多个应用程序中重复使用的组件？（A）jsp页面（B）JavaMail（C）JavaBean（D）Servlet

2.下列选项中，（）可以准确地获取请求页面的一个文本框的输入（文本框的名称为name）.(A)request.getParameter（name）(B)request.getParameter（"name"）(C)request.getParameterValues(name)(D)request.getParameterValues("name")

无屈服阶段的塑性材料，以卸载后产生数值为0.2%塑性应变（残余应变）的应力值称为名义屈服极限（屈服强度）

二只50mL容量瓶，分别为(1)、(2)，在(1)号容量瓶中加入Cd2+未知液5.0mL，测得扩散电流为10μA，在(2)号容量瓶中加入Cd2+未知液5.0mL，再0.005mol/LCd2+标准溶液5.0mL，测得扩散电流为15μA，未知溶液中Cd2+的浓度是多少(mol/L)()

13.日本人はご飯を食べる前に「（　　　　　）」とい言います。

2.TheXiaDynasty,thefirstinChinesehistory,wasestablishedinthe21stcenturyBC,headingthebeginningofaslavesocietyinChina.

Althoughmanyofusmayfeelair-conditionersbringrelieffromhot,humidorpollutedoutsideair,theyposemanypotentialhealthhazards.Muchresearchhaslookedathowthemovementofairinsideaclosedenvironment---suchasanofficebuilding---canspreaddiseaseorexposepeopleinthebuildingtoharmfulchemicals.OneofthemorewidelypublicizeddangersisthatofLegionnaire’sdisease,whichwasfirstrecognizedinthe1970s.Thiswasfoundtohaveaffectedpeopleinbuildingswithair-conditioningsystemsinwhichwarmairpumpedoutofthesystem’coolingtowerswassomehowsuckedbackintotheairintake(通风口),inmostcasesduetopoordesign.Thewarmair,filledwithbacteria,wascombinedwithcooled,conditionedairandwasthencirculatedaroundvariouspartsofthebuilding.Studiesshowedthatevenpeopleoutsidesuchbuildingswereatriskiftheywalkedpastairexhaustpipes.Largeair-conditioningsystemsaddwatertotheairtheycirculatebymeansofhumidifiers(湿度调节器).Inoldersystems,thewaterusedforthisprocessiskeptinspecialreservoirs,thebottomsofwhichprovidebreedinggroundsforbacteriawhichcanfindtheirwayintotheventilation(通风)system.Therisktohumanhealthfromthissituationhasbeenhighlightedbythefactthattheimmunesystems(免疫系统)ofapproximatelyhalfofworkersinair-conditionedofficebuildingshavedevelopedtheabilitytofightofftheorganismsfoundatthebottomofsystemreservoirs.Butchemicalscalled“biocides”areaddedtoreservoirstomakethemgerm-free,andtheyaredangerousintheirownrightinsufficientquantities,astheyoftencontaincompoundsstronglylinkedtocancers.Finally,itshouldbepointedoutthattheartificialclimaticenvironmentcreatedbyair-conditionerscanalsoaffectus.Inanaturalenvironment,whetherindoororoutdoor,therearesmallvariationsintemperatureandhumidity.Indeed,thehumanbodyhaslongbeenaccustomedtothesenormalchanges.Inanair-conditionedlivingorworkingenvironment,however,bodytemperaturesremainwellunder37℃,ournormaltemperature.Thisleadstoaweakenedimmunesystemandthusgreaterexposuretodiseasessuchascoldsandflu.2.Intheoldair-conditionedsystems,bacteriafirstdevelop______.

Imagineyouenteracarwithnosteeringwheel,nobrakeoracceleratorpedals(踏板).Underavoice-activatedcommand,yousayanaddress“Thefastestroutewilltakeus15.3minutes.ShouldItakeit?”Yousay“yes”andyouareonyourway.Thecarrespondsandstartsmovingallbyitself.Allyouhavetodoissitbackandrelax.Howweirdwoulditbeif,onedayinthefuture,everyonehadsuchacar?Nocrazydiving,noinsults,nocuttingin;trafficlawswouldberespectedanddrivingmuchsafer.Ontheotherhand,imaginethecostsavingsforlocalpoliceenforcementandtownbudgetswithoutallthosespeedingandparkingtickets.Anewtechnologyhasthepotentialtochangemodernsocietyinradicalways.There’snoquestionthatself-drivingvehiclescouldbeanenormousbenefit.Thepotentialforsafercarsmeansaccidentstatisticswoulddrop:some94%ofroadaccidentsintheU.S.involvehumanerror.Olderdriversandvisually-orphysically-impairedpeoplewouldgainanewleveloffreedom.Maintainingsafespeedsandbeingelectric,self-drivingcarswoulddrasticallyreducepollutionlevelsanddependencyonnon-renewablefuels.Roadswouldbequieter,peoplesafer.Butwemustalsoconsidertheimpactofthenewtechnologyonthosewhonowdependondrivingfortheirlivelihoods.AccordingtotheU.S.DepartmentofLabor,inMay2015therewere505,560registeredschoolbusdrivers.TheAmericanTruckingAssociationlistsapproximately3.5millionprofessionaltruckdriversintheU.S.Thecompaniesdevelopingself-drivingvehiclesshouldbepartneringwithstateandfederalauthoritiestoofferretrainingforthismassiveworkforce,manyofwhomwillbedisplacedbythenewtechnology.Thisissimilartowhat’shappeninginthecoalandoilindustries,asituationthatfuelsmuchofthecurrentpoliticaldiscontentinthiscountry.Newtechnologieswill,andshould,bedeveloped.Thisishowsocietymovesforward.However,progresscan’tbeone-sided.Itisnecessaryforthecompaniesandstateagenciesinvolvedtoconsidertheethicalconsequencesofthesepotentialchangestobuildabetterfutureforall.13.Whatwouldbethenegativeimpactofdriverlesscars?