在砖基础中，为保证基础外挑部分在基底反力作用下不致发生破坏，大放脚的砌法有( )两

已知x=2是方程ax-5x-6=0的解，则a=______．

某同学在使用电流表测量通过某一灯泡的电流的实验，闭合开关后，发现电流表的指针偏转到如图所示的位置，于是他立即断开开关．则：

（1）测量时产生这种现象的原因是____________________________________，

（2）该同学为了完成实验，下一步应该采取的措施是_____________________

（3）改正错误后，该同学再闭合开关，发现指针的读数是1.8 A，请你在图中画出指针的位置．

患者，男性，30岁。因低热、乏力、盗汗、干咳2个月前来就诊。X线胸片检查示：右肺片状阴影伴空洞。痰涂片可找到抗酸杆菌。

该病例应诊断为哪种类型的肺结核（）。

A.成人肺结核

B.晚期肺结核

C.Ⅰ型肺结核

D.Ⅱ型肺结核

E.Ⅲ型肺结核

F.Ⅳ型肺结核

G.Ⅴ型肺结核

H.其他类型

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 could stimulate 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 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're 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 Internet

Cash 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 found 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 notes and coins

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.

《化学品分类和危险性公示通则》（GB13690-2009）适用于化学品分类及其危险公示，也适用于化学品（）和消费品的标志。

A.运输过程

B.经营场所

C.生产场所

D.储存场所