招标人是依照《招标投标法》规定提出招标项目、进行招标的（）。

下面对图层蒙板的显示、关闭和删除描述哪些是正确的：

Directions:

Inthissection,thereare10incompletesentences.Youarerequiredtocompleteeachonebydecidingonthemostappropriatewordorwordsfromthe4choicesmarkedA,B,CandD.ThenyoushouldmarkthecorrespondingletterontheAnswerSheetwithasinglelinethroughthecenter.

21、62%ofthepeoplesurveyedsaidtheyalwaysavoided______theirsmartphonesduringmeals.

A.useB.usingC.touseD.used

22、TheHRdepartmentisacriticalpartofemployeewell-beinginanybusiness,nomatter______smallitis.

A.howB.whatC.whereD.which

23、Accordingtotheregulation,inspections______toensurethatthesystemsareingoodcondition.

A.demandedB.havedemandedC.bedemandedD.aredemanded

24、Beforeyouthinkaboutaskingforapromotion,makesurethateitherapositionopeningexists______anewpositionisneededtobecreated.

A.andB.norC.orD.but

25、ThetrafficwasmakingsomuchnoisethatIcouldn'thearwhathe______.

A.issayingB.wassayingC.hassaidD.willsay

26、Ourcompanycultureis______makesussuccessfulincreatingafriendlyandexcitingenvironment.

A.whereB.howC.whatD.why

27、Mostpeopleweregreatlyshockedbythenews______theITcompanyhadgonebankrupt.

A.whatB.howC.whyD.that

28、IwouldprobablytrytofindabetterjobifI______inyourposition.

A.amB.wereC.havebeenD.be

29、Ifyouare______busytoattendthemeeting,youcansendyourassistanttotakeyourplace.

A.veryB.soC.tooD.more

30、Ihadtowaitforanothertwomonthstobeabletohavethecar______.

A.fixingB.fixC.tofixD.fixed

下面对矢量图和象素图描述正确的是（）

投标人在招标文件要求提交投标文件的截至时间前，可以（）已提交的投标文件，并书面通知招标人。