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Many scientists hold that global warming can be controlled by.
A．reducing the polar bear population.
B．paying more attention to the earth's rising temperatures
C．reducing carbon dioxide emissions
D．refreezing the polar ice caps
答案
更多“Many scientists hold that global warming can be controlled by.A．reducing the polar bear po”相关的问题
第1题
Many scientists hold that global warming can be controlled by ______.
A．reducing the polar bear population
B．paying more attention to the earth's rising temperatures
C．reducing carbon dioxide emissions
D．refreezing the polar ice caps
第2题
Tidal waves have taken many human lives in the past. Today scientists can predict when a tidal wave will hit land. They use a seismograph to do this. A seismograph is an instrument that records the strength, the direction, and the length of time of an earthquake or seaquake. It is not possible to hold back a tidal wave, but it is possible to warn people that a tidal wave is coming. This warning can save many lives.
What does the Japanese word "tsunami" mean？
A．Tide.
B．Storm wave.
C．Earthquake.
D．Strong wind.
第3题
A. Right
B. Wrong
C. Not mentioned
第4题
A．the theories of scientists are used as justification for such harmful beliefs
B．only through science can these people be refuted
C．they have an obligation to correct their mistakes
D．scientists are the ones who know the true nature of humankind
第5题
根据短文回答 36～40 题。
Life in the Universe
Many scientists today are convinced that life exists elsewhere in the universe － life probably much like that on our own planet. They reason in the folio, wing way.
As far as astronomers (天文学家) can determine, the entire universe is built of the same matter. They have no reason to doubt that matter obeys the same laws in every part of the universe. Therefore, it is reasonable to guess that other stars, with their own planets, were born in the same way as our own solar system. What we know of life on earth suggests that life will arise wherever the proper conditions exist.
Life requires the right amount and kind of atmosphere. This .eliminates all those planets in the universe that are not about the same size and weight as the earth. A smaller planet would lose its atmosphere; a larger one would hold too much of it.
Life also requires a steady supply of heat and light. This eliminates double stars, or tars that flare up (闪耀) suddenly. Only single stab that are steady sources of heat and light like our sun would qualify.
Finally, life could evolve only if the planet is just the right distance from its sun. With a weaker sun than our own, the planet would have to be closer to it. With a stronger sun, it would have to be farther away.
If we suppose that every star in the universe has a family of planets, then how many planets might support life？ First, eliminate those stars that are not like our sun. Next, eliminate most of their planets; they are either too far from or too close to their suns. Then eliminate all those planets which are not the same size and weight as the earth. Finally, remember that the proper conditions do not necessarily mean that life actually does exist on a planet. It may not have begun yet, or it may have already died out.
This process of elimination seems to leave very few planets on which earthlike life might be found. However, even if life could exist on only one planet in a million, there are so many billions of planets that this would still leave a vast number on which life could exist.
第 36 题 Astronomers believe that matter in different parts of the universe（）
A．obeys different laws
B．obeys one common law
C．obeys the same laws
D．obeys no common law
第6题
请根据短文内容，回答题。
A Record-Breaking Rover
NASA&39;s Mars rover Opportunity has boldly gone where no rover has gone before-- at least in terms of distance. Since arriving on the Red Planet in 2004, Opportunity has traveled 25.01 miles, more than any other wheeled vehicle has on another world. On July 27, after years of moving about on Martian ground, the golf-cart:sized Opportunity had driven more than 24 miles, beating the previous record holder--a Soviet rover sent to the moon in 1973.＜br＞
"This is so remarkable considering Opportunity was intended to drive about 1 kilometer and was never designed for distance," says John Callas, the Mars Exploration Rover Project Manager.＜br＞
He works at NASA&39;s Jet Propulsion Laboratory in Pasadena, California. "But what is really important is not how many miles the rover has racked up, but how much exploration and discovery we have accomplished over that distance."＜br＞
Opportunity＜br＞
The solar-powered Opportunity and its twin rover, Spirit, landed on Mars I0 years ago on a mission expected to last 3 months. The objective of the rovers was to help scientists learn more about the planet and to search for signs of life, such as the possible presence of water.＜br＞
Spirit stopped communicating with Earth in March 2010, a few months after it got stuck in a sand pit. But Opportunity has continued to collect and analyze Martian soil and rocks.＜br＞
During its mission, Opportunity has captured, and sent back to Earth, some 187,000 panoramic and microscopic images of Mars with its cameras. It has also provided scientists with data on the planet&39;s atmosphere, soil, rocks, and terrain.＜br＞
Marathon Rover The rover doesn&39;t seem to be ready to stop just yet. If Opportunity can continue on, it will reach another major investigation site when its odometer hits 26.2 miles. Scientists call this site Marathon Valley, because when the rover reaches the area, it will have traveled the same distance as the length of a marathon since its arrival on Mars.＜br＞
Researchers believe that clay minerals exposed near Marathon Valley could hold clues to Mars&39;s ancient environment. Opportunity&39;s continuing travels will also help researchers as they plan for an eventual human mission to the Red Planet.
Opportunity is a record-breaking rover in the sense of __________. 查看材料
A.how long it has stayed in space
B.how far it has traveled
C.how much investment it has involved
D.how many facilities it has been equipped with
第7题
The New World monkeys, one of two major groups of monkeys, live in Central America and Africa. The strong New World monkeys have more widely space than those Old World monkeys. Most kinds of Old World monkeys have 36 teeth.All New World monkeys have 32 teeth. Some New World monkeys can hold things with their tails but no Old World monkeys can.
Monkeys use their long arms and legs to help them climb and leap. They grasp the branches of trees with their hands and feet. Most types of monkeys have a long tail that helps them keep their balance. While moving through trees, some monkeys use their tails to grasp branches.
Almost from the moment of birth, a baby monkey hangs on to its mother by grasping her fur. The infant clings to its mother's underside at first. Later it rides on her back. Until the baby can travel safely on its own, its mother carries it. A baby monkey feeds on its mother's milk. Depending on the species, a baby monkey receives its mother's milk for a few weeks up to two years.
(30)
A．Their tricks.
B．Their order.
C．Their liveliness.
D．Their intelligence.
第8题
As far as astronomers can determine, the entire universe is built of the same matter. They have no reason to doubt that matter obeys the same laws in every part of the universe. Therefore, it is reasonable to guess that other stars, with their own planets, were born in the same way as our own solar system. What we know of life on earth suggests that life will arise wherever the proper conditions exist.
Life requires the right amount and kind of atmosphere. This eliminates all those planets in the universe that are not about the same size and weight as the earth. A smaller planet would lose its atmosphere, a larger one would hold too much of it.
Life also required a steady supply of heat and light. This eliminates double stars, or stars that flare up suddenly. Only single stars that are steady sources of heat and light like our sun would qualify.
Finally, life could evolve only if the planet is just the right distance from its sun. With a weaker sun than our own, the planet would have to be closer to it. With a stronger sun, it would have to be farther away.
If we suppose that every star in the universe has a family of planets, then how many planets might support life？ First, eliminate those stars that are not like our sun. Next, eliminate most of their planets, they are either too far from or too close to their suns. Then eliminate all those planets which are not the same size and weight as the earth. Finally, remember that the proper conditions do not necessarily mean that life actually does exist on a planet. It may not have begun yet, or it may have already died out.
This process of elimination seems to leave very few planets on which earthlike life might be found. However, even if life could exist on only one planet in a million, there are so many billions of planets that this would still leave a vast number on which life could exist.
Astronomers believe that matter in different parts of the universe ______.
A．has different laws
B．has one common law
C．shares the same laws
D．shares no common law
第9题
Electric Backpack
Backpacks are convenient．They can hold your books，your lunch，and a change of clothes，leaving your hands free to do other things．Someday，if you don’t mind carrying a heavy load，your backpacks might also power your MP3 player，keep your cell phone running，and maybe even light your way home． Lawrence C．Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole3，Mass. ，have invented a backpack that makes electricity from energy produced while its wearer walks．In military actions，search-and-rescue operations，and scientific field studies，people rely increasingly on cell phones，global positioning system（GPS） receivers，night-vision goggles，and other battery-powered devices to get around and do their work．The backpack’s electricity-generating feature could dramatically reduce the amount of a wearer’s load now devoted to spare batteries，report Rome and his colleagues in the Sept．9 Science．
The backpack ’s electricity-creating powers depend on springs used to hang a cloth pack from its metal flame．The frame. sits against the wearer’s back，and the whole pack moves up and down as the person walks． A gear mechanism converts vertical movements of the pack to rotary motions of an electrical generator，producing up to 7.4 watts．
Unexpectedly．tests showed that wearers of the new backpack alter their gaits in response to the pack ’s oscillations．so that they carry loads more comfortably and with less effort than they do ordinary backpacks．Because of that surprising advantage，Rome plans to commercialize both electric and non—electric versions of the backpack．
The backpack could be especially useful for soldiers，scientists，mountaineers，and emergency workers who typically carry heavy backpacks．For the rest of us．power—generating backpacks could make it possible to walk，play video games，watch TV，and listen to music，a11 at the same time．Electricity-generating packs aren’t on the market yet，but if you do get one eventually，just make sure to look both ways before crossing the street!
第 1 题 Backpacks are convenient because
A．they can be very large
B．they can hold as many things as you want to carry．
C．your hands are freed t0 do other things．
D．you do not have to carry things with you．
第10题
Which of the following could be the title of this passage？
A．The Sleepless Elite.
B．The Impact of Sleep on Health.
C．A New Research on Sleep.
D．Manipulation of Sleep Pathways.
