已审定的施工组织设计，由()报送建设单位A、承包单位 B、总包单位 C、项目经理部

.在均匀介质中选取平衡位置在同一直线上的9个质点,相邻两质点的距离均为,如图11(a)所示,一列横波沿该直线向右传播,时到达质点1,质点1开始向下运动,经过时间第一次出现如图11(b)所示的波形.则该波的周期为      ,波速为      。  

阅读材料，回答问题。

在互联网和手机媒体加速信息交流、促进知识创新、推动经济发展的同时，网络和手机媒体上也出现了一些黄色流毒，或者发布他人隐私、虚假信息等不良文化现象，危害青少年健康成长。党中央强调要为青少年创造文明健康的网络环境，在全社会树立良好的网络道德风尚。为次某校发出了中学生文明上网倡议书。

（1）指出材料中违背的网络伦理原则。（4分）

（2）运用公民道德知识，结合材料说明中学生应怎样文明上网？（6分）

* * 壁的结构是（）。

A．横纹皱襞及弹力纤维

B．纵纹皱襞及弹力纤维

C．横纹皱襞及平滑肌纤维

D．黏膜层、纤维层和脂肪层

E．黏膜层、肌层和纤维层

阅读理解。

     They like using the Internet.They have lots of pocket money to spend.And they spend a higher

proportion of it online than the rest of us.Teenagers are just the sort of people an online seller is

interested in, and the things they want to buy－games, CDs and clothing－are easily sold on the

Web.

     But paying online is a tricky business for consumers who are too young to own credit cards.

Most have to use a parent's card.They want a facility that allows them to spend money.

     That may come sooner than they think: new ways to take pocket money into cyber (网络的)

space are coming out rapidly on both sides of the Atlantic.If successful, these products can stimulate

(刺激) online sales.

     In general, teenagers spend huge amounts: $153bn (billion) in the US last year and ￡20bn annually

in the UK.Most teenagers have access to the Internet at home or at school --- 88 percent in the US,

69 percent in the UK.According to the Jupiter Research, one in eight of those with Internet access has

bought something online---mainly CDs and books.

     In most cases, parents pay for these purchases with credit cards, an arrangement that is often

unsatisfactory for them and their children.Pressing parents to spend online is less productive than pressing

on the high street.They are more likely to ask "Why?" if you ask to spend some money online.

     One way to help teenagers change notes and coins into cybercash is through prepaid cards such as

InternetCash in the US and Smart cards in the UK.Similar to those for pay-as-you-go mobile telephones,

they are sold in amounts such as￡20 or $50 with a concealed 14-digit number that can be used to load

the cash into an online account.

1.What does the word "They" in paragraph 1 refer to?

A. Sellers.

B. Buyers.

C. Teenagers.

D. Parents.

2. According to the passage, which of the following statements is TRUE?

A. More than half of the teenagers in the US and the UK have Internet access.

B. Teenagers pay for goods online with their own credit cards.

C. Most teenagers in the US and the UK have bought something online.

D. Teenagers find it easier to persuade parents to buy online than in a shop.

3. A new way to help teenagers shop online is to use ______.

A. a new machine

B. special coins and notes

C. prepaid cards

D. pay-as-you-go mobile phones

4.What is the passage mainly about?

A. Online shopping traps.

B. Internet users in the US and the UK.

C. New credit cards for parents.

D. The arrival of cyber pocket money.

词语的特点有哪些？