低压多级离心泵的转子部分主要由轴，叶轮，平衡盘及（）等零件组成。A.密封环 B.轴套

Like every other Olympics, the London 2012 Olympics will depend upon thousands of volunteers to help with the smooth running of the event. To show the importance of the role, London 2012 volunteers are to be called ‘Game Makers’. Lord Coe has said recently: “London 2012 is relying on brilliant Game Makers to help us create a great Olympic and Paralympic Games. ”

London 2012 Olympics volunteers will provide the face of London 2012, working behind the scenes and making sure the games are as well organized, efficient and, most importantly, as enjoyable as possible.

Despite the hard-work and often unsociable hours required of volunteers, applications to be considered as a Game Maker were unprecedented（空前的） with all the 70, 000 available positions applied within days. But, for those still interested in helping out during 2012 and being in the middle of the action, there are still a lot of opportunities available.    

If you were one of those who missed out on the chance of becoming London 2012 volunteers, you can now apply to be one of the 8, 000 London Ambassadors（大使）. This important role involves greeting fans from all over the world, welcoming them to the fantastic capital city of London and providing a friendly face as well as help, advice and a good old traditional warm British welcome. The view of London most visitors take away with them after the 2012 Olympics will mostly be down to the volunteers and ambassadors, so these roles play a very important part in the process of making the UK a great place to travel to.    

Becoming a London Ambassador is a brilliant way to be involved with the London 2012 volunteers scheme and become a part of what should be an historic summer.

小题1:Why are London 2012 volunteers called “Game Makers”?

A．They’ll decide whether the London 2012 Olympics are a success.

B．They play an important role in the London 2012 Olympics.

C．The London 2012 Olympics won’t be organized without them.

D．They will work hard and effectively.小题2:Which of the following can replace the underlined part “be down to” in Paragraph 4?

A．be the responsibility of

B．be under the control of

C．be in harmony with

D．be in charge of小题3:What’s the purpose of the passage?

A．To appeal to more volunteers.

B．To introduce the London 2012 Olympics.

C．To show the importance of volunteers.

D．To guide how to spend the historic summer.

下列事实，最能说明物质吸收的热量跟物质种类有关的是（　　）

A．体积相同的两杯水温度都升高了10℃，它们吸收的热量相同

B．质量相等的两块铜温度分别升高5℃和10℃，它们吸收的热量不相同

C．体积相等的水和煤油温度都升高10℃，它们吸收的热量不相同

D．质量相等的水和铜温度都升高10℃，它们吸收的热量不相同

写出符合下列要求的有机物的结构简式：

（1）燃烧后生成CO₂和H₂O的物质的量之比为2的两种常见的烃：_________，_________；一种常见的烃的含氧衍生物：______________。

（2）燃烧后生成H₂O和CO₂的物质的量之比为2的一种常见的烃：_________。

（3）不能脱水生成烯烃的碳原子数小于6的两种饱和一元醇：_____________，____________。

（4）氧化后生成乙酸的醛：__________；加成后生成乙二醇的醛：___________。

（5）[ CH₂－O ]n的单体：___________；丙烯聚合后的高分子：__________。

强心苷的适应证，除外（）

A.慢性心功能不全

B.心房纤颤

C.心房扑动

D.室性心动过速

E.室上性心动过速

各级行应专夹保管客户风险等级分类相关资料，保管期限暂定为（）保存。

A.3

B.5

C.15

D.永久