共阳极数码管的公共端通常接高电平。()

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

13.日本人はご飯を食べる前に「（　　　　　）」とい言います。

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?

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?

80C51单片机的堆栈区只可设置在()。

MCS-51单片机串行端口有四种工作方式，其中方式1为()。

80C51CPU是()位的单片机。

在单片机中，通常将一些中间计算结果放在()中。

单片机80C51的XTAL1和XTAL2引脚是()引脚

下面关于8051单片机内部寄存器功能的描述，正确的为()

8051单片机中，唯一一个用户可使用的16位寄存器是()

8031单片机复位后，程序计数器P0--P3口的内容是()。

通过示波器观察ALE引脚的状态，可以大致判断MCS-51单片机是否正常工作。

有以下程序main(){intp[8]={11,12,13,14,15,16,17,18}，i=0,j=0;while(i++<7)if(p[i]%2)j+=p[i];printf("%d",j);}程序运行后的输出结果是（　）