[听力原文] 男：女儿怎么不太高兴啊？ 女：明天下午幼儿园的表演她希望我们都去看。 男：怎么？你去不了了？ 女：本来没问题，但电台临时通知我开一个会。 男：必须参加吗？明天咱们女儿有表演啊。 女：我也很想去，但是明天的会议要讨论我的节目，所以我必须得出席。 男：那就没办法了。你别担心，我去安慰安慰她。 女：好的，这事儿就交给你了。 关于女的，可以知道什么？（）
A．不爱看电视
B．在电台工作
C．现在去开会
D．要参加表演
参考答案：B
Passage Four
| Global climate change, often seen as a process stretching over thousands of years, could in fact occur abruptly and unexpectedly-quickly pushing up temperatures by as much as 18 degrees Fahrenheit and wreaking havoc(大破坏，浩劫) on human society, scientists warned on Wednesday. "Climate change is not always smooth. Sometimes it is abrupt," said Richard Alley, a climate expert at Pennsylvania State University and lead author of a new National Academy of Sciences report on the threat of rapid climatic shifts. "If you have a very large, abrupt change, a lot of people and a lot of ecosystems are going to notice," he said．"The bigger and faster it is, the harder it will be to deal with." The new National Academy of Sciences report, released this week, warns that gradual global warming coupled with other human impacts on the environment could "trip the switch" for sudden climate change. At the American Geophysical Union meeting on Wednesday, Alley and other environmental scientists said the geological evidence indicated that such rapid climate shifts had occurred frequently in the past—moving temperatures drastically in the space of just a few decades. "This can happen in less than a human generation, and then it will persist for thousands of years," said David Battisti, an atmospheric scientist at the University of Washington. The most immediate dangers posed by abrupt climate change range are devastating droughts and floods which could seriously affect both water supply and agriculture across vast stretches of the planet. Longer term impacts could include changes in the basic systems which determine regional global temperatures. Scientists believe that the Gulf Stream, a current (水流) of warm Atlantic water which now keeps much of Northern Europe temperate, could theoretically reverse direction if enough cool fresh water runs into the north Atlantic from melting ice, a change that would quickly impact European weather. |
One of the most immediate dangers posed by abrupt climate change is______.
A．disastrous droughts and floods
B．extinction of animals and plants
C．disappearance of agriculture
D．rising sea level
，则为使粒子不从外圆飞出，则可以控制导轨区域磁场的宽度S（如图乙所示），那该磁场宽度S应控制在多少范围内