The devastation caused by Hurricane Katrina is a wake-up call. It is a call for every American to pay attention to the destruction we risk by allowing human-induced(导致的) climate change to continue. It is impossible to prove that Hurricane Katrina was caused by global warming, or even that human activities made the storm more severe. However, a paper published in the scholarly journal Nature reports that the force of dangerous hurricanes has increased by 50% during the last 50 years. It also reports that a global warming-induced rise in temperature near the ocean’s surface has probably contributed to this increase in dangerous storms, and thus to property(财产) damage and human death.
On August 30, the Los Angeles Times summed up(总结) the view of many scientists who agree that if the frequency of hurricanes does not decrease in the next few years, then we will be fairly certain that humans, and not natural storm cycle, are at the root of the problem. I believe there is at least a chance that by reducing U.S. reliance on fossil fuels for energy, we can prevent future tragedies like Hurricane Katrina. Let the change begin now.
There are many ways to reduce the volume of greenhouse gas emissions. My family drives the most fuel-efficient car we can afford, but I prefer to take public transportation whenever possible. My family buys locally grown food instead of produce that was transported thousands of miles on fuel-burning vehicles. We also replaced our incandescent light bulbs（白炽灯泡）with more energy-efficient compact fluorescents（荧光灯）. This might sound like a trivial move, but the Union of Concerned Scientists reports that if every household in the United States replaced one incandescent bulb with a compact fluorescent, it would have the same effect on U.S. carbon-dioxide emissions as removing 7.5 million cars from the roads. Now think if every household replaced not just one but all of their incandescent bulbs!
The United States, with just five percent of the world’s population, is responsible for close to one quarter of greenhouse gas emissions worldwide, yet our country is doing far less than most European nations to fight global warming. We don’t have to sacrifice our lifestyles; Europeans enjoy the same standards of living as Americans. So what are we waiting for? It is time to act.
小题1: Which of the following is a fact?
A．Hurricane Katrina was caused by global warming.
B．Human activities made the storm more severe.
C．The force of dangerous hurricanes has increased by 50 percent during the last 50 years.
D．A global rise in temperature near the ocean’s surface accounts for more dangerous storms.小题2:From Paragraph 2 we can infer that many scientists agree ________.
A．it might be human activities that lead to global warming.
B．natural storm cycles have caused global warming.
C．hurricanes are likely to come more frequently.
D．burning fossil fuels for energy is a better alternative.小题3: If every household in the U.S. replaced all their incandescent bulbs, ________.
A．it would have the same effect as removing 7.5 million cars from the roads.
B．it would save 7.5 million tons of carbon-dioxide from going into the air.
C．this would reduce the total output of CO₂emissions in huge amounts.
D．cars will be much more environmentally friendly.小题4: According to the writer,_______in reducing the volume of greenhouse gas emissions.
A．Europe does a better job.
B．Europe should follow the example of America.
C．he, as an European, wants to see more efforts made by Americans.
D．Europeans should shoulder a greater responsibility.
①（1分）
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, 由平抛物体运动规律：
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，即有
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，
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，B进入传送带上开始匀减速运动，设B减速到
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，B以速度vB进入传送带上匀加速至
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恒成立，
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