问题
选择题
“生命可贵，安全第一”．下列采取的安全措施错误的是（ ）
A．厨房煤气管道泄漏，立即关闭阀门并开窗通风
B．自来水厂给饮用水消毒，可使用硫酸铜
C．做甲烷燃烧实验前，应先检验甲烷纯度
D．进入久未开启的菜窖，先用蜡烛做灯火试验
答案
答案：B
搜题请搜索小程序“爱下问搜题”
“生命可贵，安全第一”．下列采取的安全措施错误的是（ ）
A．厨房煤气管道泄漏，立即关闭阀门并开窗通风
B．自来水厂给饮用水消毒，可使用硫酸铜
C．做甲烷燃烧实验前，应先检验甲烷纯度
D．进入久未开启的菜窖，先用蜡烛做灯火试验
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