目前世界上许多国家已经消除了脊髓灰质炎，我国属于下列哪一种情况（） A.尚未流行 B

保证铁路无缝线路冬天钢轨不被拉断、夏天不发生胀轨跑道的轨温为(　)轨温。

A．零应力

B．中间

C．设计锁定

D．施工锁定

D

Mayor Boris Johnson Monday outlined plans to make London “the cleanest, greenest city on Earth” by the 2012 Olympics and called for commitments from other world cities at a climate change conference. Leaders of the world’s 40 largest cities are meeting in Seoul this week for a summit on combating global warming –the third to be held since 2005.

“What we should do in Seoul is that we will stop the endless addiction of mankind to the internal combustion engine (内燃机),” said Johnson. He said at a press conference the world’s cities consume 75 percent of the world’s energy and produce 80 percent of the emissions which cause climate change. “The problem of our planet is an urban problem,” Johnson said.

He said the British capital wants to use the Olympics” to drive the greeting and the improvement of our city and noted that London is committed to reduce carbon dioxide emissions by 60 percent by 2025.

Johnson said the key measure was being taken to solve problems relating to housing and commercial buildings, which accounted for 70 percent of carbon dioxide emissions in London. This involved retrofitting (翻新) ---installing lagging – in large numbers of public buildings.

Johnson proclaimed himself a “passionate cyclist” and said he would push ahead with cycle superhighways around London.

London’s air quality problem, he said, was caused by vehicle emissions from 8,300 worn and used diesel (柴油buses, which could be replaced by low-carbon vehicle. In addition, there were also 32,000 taxis running on diesel fuel, which could be replaced by electric vehicle.

Johnson said there would be a few programs in the next few years to produce a “cleaner, greener” bus for the city. “The age of the diesel bus has got to be over in London.”

68. Which of the following statements is NOT TRUE according to this passage?

London’s air quality will be improved in the near future.

The used buses running on diesel will be replaced by electric vehicles.

London promises to reduce carbon dioxide emissions by 60 percent by 2025.

Something has been done to solve the problem of carbon dioxide emissions.

69What does the underlined word mean in the first paragraph?

A. resisting     B. supporting   C. agreeing        D. solving

70. The topic of the meeting in Seoul might be _____.

A. climate change                        B. global warming

C. London Olympics in 2012               D. green environment

71. If the passage was continually written, the following might be ______.

A. measures to end the age of the diesel bus

B. measures to reduce carbon dioxide emissions in London

C. measures to solve housing and commercial items

D. measures to replace the old and used vehicles

在计算机网络的拓扑结构中，不属于点一点式网络的是( )。

A．星型结构

B．环型结构

C．网型结构

D．总线型

右锁骨上淋巴结收集下列哪些区域的淋巴液（）

A.食管、胃

B.躯干上部、乳腺、胸壁处淋巴结

C.右侧鼻咽部淋巴结

D.气管、胸膜、肺等处淋巴结

E.口底、颊黏膜、齿龈等处淋巴结

ECU利用（）的信号可以监测发动机某个汽缸存在失火现象。

A.曲轴位置传感器

B.凸轮轴位置传感器

C.氧传感器

D.爆震传感器