When we look at the sky and see a bright light moving quickly across it or coming towards the earth, we talk about seeing a “shooting star” or a “falling star”. These moving lights are not, in fact, stars at all. They are small pieces of matter from outer space, which burn up as they enter the Earth’s atmosphere. The correct name of them is meteoroids. Any pieces that make it to the Earth’s surface without completely burning up are known as meteorites. A meteor is actually the name given to the light we see when a meteoroid is burning up.
When a meteorite hits the Earth at speeds between 11 and 72 kilometers a second, it can do amazing damage. A very large meteorite could knock the earth out of its orbit. If this happened, all life on Earth would probably become extinct（灭绝）. The path we follow around the Sun would change and as a result the Earth would become either much hotter or much colder. This change in temperature would affect sea levels and the amount of water in rivers. There would either be huge floods, which would cover most of the land with water, or the oceans would dry up and there would be a drought, which means a long period of time without rain. Either way, nothing could survive. If a large meteorite landed in the sea it would almost certainly cause tsunamis, which would race towards the land, destroying everything in their paths.
Although it is unlikely the Earth will be struck by a meteorite large enough to do that kind of damage, there is evidence of fairly large meteorites hitting the Earth in the past. In 1908 a large area of forest in Tunguska, Siberia was destroyed by a meteorite that came apart just before it hit the ground. The moon, however, has about three billion craters陨石坑caused by meteorites impacting影响 its surface. The reason more meteorites have reached the surface of the moon than the surface of the Earth is that the moon does not have enough atmosphere for the meteorites to burn up in. some of the meteorites that have reached the Earth’s surface have done considerable damage. Some scientists believe it was a change of climate caused by meteorites hitting the Earth that resulted in the extinction of the dinosaurs and other large prehistoric animals.
Scientists are especially interested in meteorites because they contain information about the solar system. It is widely believed by scientists that most meteorites are produced by collisions（碰撞） between asteroids (small planets). These collisions probably happened many billions of years ago. This means the physical and chemical structure of a meteorite can give scientists information about the early days of the universe.
【小题1】          The story is about ___.     

Against the supposition that forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.
This finding suggests that taking steps to prevent northern forest fires to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over the next several centuries as a result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.
This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.
Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone（臭氧） levels increased, and ash from the fire fell on far-off sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.
“We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere.” Scientists tracked the change in the amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicted, 0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.
【小题1】According to the new findings, taking steps to prevent northern forest fires may __________.

       At one time, computers were expected largely to remove the need for paper copies of documents（文件）because they could be stored electronically. But for all the texts that are written, stored and sent electronically, a lot of them are still ending up on paper.

       It is difficult to measure the quantity of paper used as a result of Internet-connected computers, although just about anyone who works in an office can tell you that when e-mail is introduced, the printers start working overtime. “I feel in my bones this revolution is causing more trees to be cut down,” says Ted Smith of the Earth Village Organisation.

       Perhaps the best sign of how computer and Internet use pushes up demand for paper comes from the high-tech industry itself, which sees printing as one of its most promising new markets. Several Internet companies have been set up to help small businesses print quality documents from a computer. Earlier this week Hewlett-Packard Co. announced a plan to develop new technologies that will enable people to print even more so they can get a hard copy of a business document, a medical record or just a one-line e-mail, even if they are nowhere near a computer. As the company sees it, the more use of the Internet the greater demand for printers

Does all this mean environmental concerns （环境问题） have been forgotten? Some activists suggest people have been led to believe that a lot of dangers to the environment have gone away. “I guess people believe that the problem is taken care of, because of recycling （回收利用）,”said Kelly Quirke, director of the Rainforest Action Network in San Francisco. Yet Quirke is hopeful that high-tech may also prove helpful. He says printers that print on both sides are growing in popularity. The action group has also found acceptable paper made from materials other than wood, such as agricultural waste.

72.   The growing demand for paper in recent years is largely due to ___________.

A.    the rapid development of small businesses    B. the opening up of new markets

C.    the printing of high quality copies               D. the increased use of the Internet

73.   Environmentalists believe one possible way of dealing with the paper situation is ______.

A.    to encourage printing more quality documents

B.    to develop new printers using recycled paper

C.    to find new materials for making paper

D.    to plant more fast-growing trees

74.   Hewlett-Packard Co. has decided to develop new technologies because ___________.

A.    people are concerned about the environment

B.    printers in many offices are working overtime

C.    small companies need more hard copies

D.    they see a growing market for printers

75.   What would be the best title for the text?

A. Computers and Printers                                B. E-mail and the Business World

C. Internet Revolution and Environment                 D. Modern Technology and New Markets

Against the supposition that forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.
This finding suggests that taking steps to prevent northern forest fires to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over the next several centuries as a result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.
This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.
Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone（臭氧） levels increased, and ash from the fire fell on far-off sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.
“We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere.” Scientists tracked the change in the amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicted, 0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.
【小题1】．According to the new findings, taking steps to prevent northern forest fires may __________.

III．阅读理解（满分50分）
　　阅读下面短文，从每题所给的A、B、C和D项中选出最佳选项，并在答题卡上将该项涂黑。
A
Against the supposition that forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.
This finding suggests that taking steps to prevent northern forest fires to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over the next several centuries as a result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.
This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.
Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone（臭氧） levels increased, and ash from the fire fell on far-off sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.
“We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere.” Scientists tracked the change in the amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicted, 0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.
41. According to the new findings, taking steps to prevent northern forest fires may __________.
A. result in a warming climate          
B. cause the forest fires to occur more frequently
C. lead to a longer fire season            
D. protect the forests and the environment there
42. The following are all the immediate effects after a forest fire EXCEPT __________.
A. large amounts of greenhouse gases enter the atmosphere
B. the levels of ozone which is a type of oxygen increase
C. snow on the ground mirrors more sunlight back into space
D. ashes from the fire fall on the ice surface and take in more radiation from the sun
43. Earlier studies about northern forest fires __________.
A. analyze all aspects of how northern fires influence climate
B. indicate that forest fires will pollute the atmosphere
C. suggest that people should take measures to protect environment
D. suggest that the fires will speed up climate warming
44.The underlined phrase “soak up” in the last paragraph most probably means __________.
A. released         B. absorbed       C. created      D. distributed
45. From the passage we can draw a conclusion that forest fires in Alaska, Canada and Siberia may __________.
A. warm the climate as the supposition goes
B. allow more snow to reflect more sunlight into space and thus cool the climate
C. destroy large areas of forests and pollute the far-off sea ice
D. help to gain more energy rather than release more energy