要给演示文稿设置密码，需在“选项”对话框中选择“______”选项卡。A．安全性 B

生物探究课上，王华同学边用眼观察用右手记录实验现象，下图能表示她使用显微镜观察的正确方法是（　　）

A．

B．

C．

D．

情景交际， 当适择选框方从中的句子补全对话。

A. You will have a good time. B. And can you make some food for us? C. Will you help me organize it? D. There's a test tomorrow. E. I'm going to take a bus to the party. F. Let's have it today after class. G. I don't think we should watch a video. W: Hi, Mark. I want to have a class party. __1 _  M: Sure, Andrea. I can help you. So when shall we have the party? W:   _2 _  M: No, today is too early. If we have it today, half the class won't come. W: Okay. Let's have it tomorrow. M: Hmm...  _ 3   Students will leave early to study for the test. Let's have it on the weekend. W: Okay. Let's have it on Saturday afternoon. We can all meet and watch a video. M: No,   _4   Some students will be bored. Let's play party games. W: Okay, good idea. Can you organize the party games? M: Sure．I can do that.    5  _ W: Yes. That's no problem. 1.  ___  2. ___   3. ___   4. ___   5.__ __

从多普勒频谱图上能了解到血流的参数是（）。①血流性质②时相③方向④速度

A.①②

B.③④

C.①②③④

D.①④

在特殊情况下，首长可以直接决定对部属实施奖励，但事后应当向党委（支部）报告，并对此负责。（）

[背景材料]

某学校教学大楼项目是依法必须进行招标的项目，共有甲、乙、丙和丁4家潜在投标人。该项目招标人整理完招标文件的澄清与修改后，在投标截止时间前15日打电话要求各潜在投标人前来招标人所在地进行签收和领取。在规定的时间内，甲、乙2家投标人没有到招标人所在地进行领取，其中投标人甲要求招标人在规定的时间内以传真方式发给其招标文件的澄清与修改，招标人及时传真给了该投标人澄清与修改的内容；投标人乙则一直到开标前2日才来领取。开标后，投标人甲、乙分别进行了质疑与投诉，理由是招标人没有在投标截止时间前15日将招标文件的澄清与修改送达投标人，直接影响了其投标结果，要求有关行政监督部门宣布中标结果无效，并判定招标人依法重新招标。

[问题]

招标人在发出招标文件的澄清与修改环节中是否存在问题，为什么