儿童脑发育速度开始减慢、脑的大小达到成人的80%的年龄期是（） A.新生儿期 B.婴

下列关于分子的叙述中，不正确的是（　　）

A．是构成物质的一种粒子

B．能保持物质的性质

C．有固定的组成

D．在化学变化中可分

甲同学欲采用下列器材准确测定一个阻值大约为20 Ω的电阻。

A．直流电源(10 V，内阻不计)；

B．开关、导线等；

C．电流表(0～3 A，内阻约0.03 Ω)；

D．电流表(0～0.6 A，内阻约0.13 Ω)；

E．电压表(0～3 V，内阻约3 k Ω)；

F．电压表(0～15 V，内阻约15 k Ω)；

G．滑动变阻器(0～10  Ω，额定电流2 A)；

(1)为测量准确，电流表应选用________，电压表应选用________(填代号)；

(2)为了获得尽可能多的数据，该同学采用了“滑动变阻器分压接法”以调节电压，请画出正确的实验电路图，并将图中的元件按正确的实验电路图连成实物电路；

(3)闭合开关，逐次改变滑动变阻器滑动头的位置，记录与之对应的电流表的示数I、电压表的示数U。某次电流表、电压表的示数如图甲所示。                                                  

处理实验数据时，制作如图乙所示的I－U坐标图，图中已标注出了几个与测量对应的坐标点。请将与图甲读数对应的坐标点也标在图乙中，并在图乙中把坐标点连成图线；

(4)根据图乙描绘出的图线可得出这个电阻的阻值为R＝________  Ω。

Loma just had to get in touch with someone: “I had to tell my best

friend something important. I tried calling her but I couldn’t get through. So I sent her an e-mail and then I spoke to her on MSN. Without technology I would not have been able to tell her. ”

Staying connected with friends and family is important for us. That’s

why we asked our readers to tell us how cell-phones, e-mail, blogs, text messaging, and personal pages help them keep in touch. More than 1,500 responded.

Most of them told us they couldn’t live without technology: 80％of

teens said they need technology to stay in touch. Almost 30％said they’d be completely out of their friends without their cell-phones and other methods of communication.

What do they do when they’ve got news they need to share now? Most

teens say they try to reach their friends by phone. But if they don’t reach them, they use QQ, e-mails, and text messaging to get the words out.

Lots of people use one way of communication—like text messaging—to

get a friend’s attention and then use another where they can talk more. “My friends and I always tell each other everything that happens. So I send them text messages to tell them to come online so we can talk about it,” said Sabeiha.

“When planning to get together with friends”, Julian said, “the easiest

and fastest way I know is to send a text message to my contact group.”

Jocelyn said. “If I want to go to see a movie with a few friends, I usually

send text message to them. By telephone, you have to call every single friend

one by one. But text messaging allows you to send the same message to as

many as you’d like, which saves a lot of time. ”

小题1:Which of the following is NOT mentioned in the passage?

A．E-mails.

B．Blogs.

C．Personal pages.

D．Personal letters.小题2:What do most young people use first when they have news to tell their friends?

A．MSN.

B．QQ.

C．Phones.

D．Text message.小题3:The underlined part “get the words out” means“     ”.

A．send the message

B．send the e-mail

C．talk with their friends

D．meet their friends小题4: In which part of a newspaper can you find this passage?

A．Sport.

B．Education.

C．Technology.

D．Culture.

全面推进依法治国的重点是（）。

A、保证法律严格实施

B、完善社会主义法律体系

C、守法

D、学法

以下管件不能实现管线变径的是（）

A.大小头

B.活接头

C.异径管箍

D.内外丝