电焊工被强烈的（）短时间照射会使眼睛发光、疼痛，一时看不清东西，通常称“晃眼”A、紫

组成一个完整的计算机系统应该包括______。

A．主机、鼠标器、键盘和显示器

B．系统软件和应用软件

C．主机、显示器、键盘和音箱等外部设备

D．硬件系统和软件系统

随土壤深度的加深，CO²含量浓度加大。

以下是根据来访者需求确定的培训目标，哪一项符合要求？（）

A.能够掌握打字技术

B.能够进行打字操作

C.能够提高打字速度和准确率

D.能够进行汉字输入，到达每分钟120字，准确率95%以上

A

Hello,everyone. Because of the high rate of school violence(力)in some areas, teenagers’ safety becomes a serious problem. We are planning to set up an organization named School Watch to make sure that students have a safe school environment. Please be part of our plan!
What is School Watch
School Watch is a volunteer project in our school. It helps us stop violence and improve the quality of school life. It will keep yourself and your schoolmates safe. The other members of School Watch care for you and your classroom and you do the same for them.
Is it for everyone
Anybody can become a member of School Watch because everyone has something to offer.
What else can it do
School Watch makes it possible for us not only to help each other But also to make friends with each other. Some members may offer to help schoolmates who have problems with their homework.
Who is the Best School Watcher
Our school will look for the Best School Watcher and give him or her lots of prizes. You could be the one !
How do you start
To be part of this plan, the only thing you need to do is to talk to the director of the plan in your grade. If you want to get more information, check the official website at www.schoolwatch.com.

The Best School Watcher will get a lot of prizes from ______ every year.

A．the school

B．the website

C．the organization

D．the society

曲线f(x)=(x-1)(x+2)(2-x)与x轴围成的平面图形的面积为（）。

A.A

B.B

C.C

D.D