TCP和UDP都是传输层的协议。

计算机内传输的信号是数字信号，电话传输的是模拟信号。（）

21.微信支付是电子支付的一种。（）

企业只能用税后利润弥补亏损。 ( )

21.未按照招标文件要求提交投标保证金的投标文件无效。

叠合楼盖接缝处预制板侧伸出的纵向受力钢筋应在后浇混凝土叠合层外锚固。

标志着毛泽东思想初步形成的重要文章主要有：

习近平新时代中国特色社会主义思想是新时代中国共产党的思想旗帜，是国家政治生活和社会生活的根本指针，是引领中国、影响世界的当代中国马克思主义、21世纪马克思主义。

15.在信用证没有特殊规定的情况下，运输单据出单日期后21天内必须提交银行议付，否则银行拒绝付款（）

系统结构图是精确表达程序结构的图形表示法。因此，有时也可以将系统结构图当作系统流程图使用。

21.纳税人采取以旧换新方式销售货物的，可以从新货物销售额中减除收购旧货物所支付的金额。（）

6．一国国际收支有长期和大量的顺差可能会导致该国的货币升值

ReyesGuana,42,grewupinapoorMexicanfamily.Hehassevenbrothersandsisters.Hisparentsalwayshadtwojobstomakeendsmeet.Asaboy,Guanahadagoodrelationshipwiththeschoolcleaner.Hecalledher“Nick”becausesheworeNikeshoes.TheboylikedhowNikemadeeverythingclean.Hetoldherhewantedtobeacleaner,too.“Wellit’sgoodifyouwanttobeacleaner.”NiketoldlittleGuana,“Butmakesureyougotocollege.”Guanaalsolookeduptotheprincipal(校长)ofhisschool.Theschoolleadertoldtheboythathisjobwastohelpstudentsandteachers.“Wow,whenIgrowup,Iwanttodowhatyou’redoing.”Guanatoldhim.“Well,ifyousticktoyourdream,youwill,”theprincipalreplied.AndGuanareallygotthere.Butitwasquitealongjourneyforhim.Twenty-threeyearsago,hefollowedinNike’sfootstepsandwascleaningschools.Heworkedatthreeschoolstopayforhiscollegeeducation.Heheldthatjobforfouryearsandthenworkedhiswayuptobeingaschoolsafetymonitor.Afterthat,heworkedasateacherforafewyears.Now,asaprincipal,Guananeverforgetswherehecamefrom.Hehelpsstudentsfrompoorfamiliesandshowsrespect(尊重)foreveryschoolsstaffmember.Healwaysinviteseveryonetoschoolparties,includingthosewhocleanthefloorsandthosewhodrivetheschoolbuses.21.Guanahopedtobeacleanerbecausehe___________.

PassagethreeSafetyisveryimportantinschools,however,accidentsoftenhappen,sotheremustbepeopleatschoolwhoknowhowtodofirstaid.Firstaidishelpthatyougivetosomeonewhohassuddenlyfallenillorwhohashadanaccident.Youdon’thavetobeadoctororanurse.Anyonecanbeafirstaider(that’ssomeonewhoknowsfirstaid),butinmostschools,theonlyfirstaidersareteachers.Therearealotmorechildrenthanteachersinanyschool,sowhynotteachthechildrenfirstaid?That’sexactlywhatwe’vedoneinmyownschool.Theschool’steamoffirstaidersnowhasthirty-twomembers,someasyoungaseleven,whoknowwhattodowhensomeoneisindanger.Everyyearnursesfromalocalhospitalteachourchildrenthenecessaryskillstosavelives.Childrenaretaughtwhattodo,forexample,ifafriendoftheirshasaheadache.Theyknowhowtocleanandcoveracutifsomeonehurtsthemselvesdoingsport.Theyalsoknowwhattodoifsomeoneisinrealdanger.Recently,twostudentsfrommyschoolwereabletousetheirnewskills.13-year-oldMikeandhisfriendJoewereplayingtogetherwhenJoegotapieceofappleinhisthroatthatwouldn’tmove.Althoughhisfriendwasingreatdanger,Mikewasnotfrightened.Withonemove,hetooktheappleoutandsavedJoe’slife.11-year-oldKim’sstoryisevenmoreamazing.Hermumsuffersfromaheartproblem.Oneevening,hermumsuddenlyfelltotheground.Kimknewexactlywhattodo.Shecalledanambulanceandtookcareofhermumuntilhelparrived.Withthenecessaryfirst-aidknowledge,thestudentsdidareallygoodjob.21.Whatmaythewriterprobablybe?

1.齿轮泵可以通过改变转速改变流量，故属于变量泵。（）