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A.Microwaves are the medium WMAP used to make measureme……

Cosmology is sometimes pooh-poohed as more philosophy than science. It asks deep questions about nature but provides unsatisfyingly vague answers. The cosmos may be 12 billion years old, but it could be as much as 15 billion. The stars began to shine 100 million years after the Big Bang, or maybe it’s a billion. "Our ideas," acknowledges Max Tegmark of the University of Pennsylvania, "have been kind of wobbly."
But much of the wobble has been fixed, thanks to a satellite known as the Wilkinson Microwave Anisotropy Probe, or WMAP. Since July 2001, WMAP has been orbiting in deep space, more than a million kilometers from Earth, studying the most ancient light in existence. And in a dramatic reminder that important space science is almost always done by machines, not fragile humans, it reported a series of precision measurements that will finally put cosmology on a firm foundation.
What the satellite found, says Princeton University’s David Spergel, a theorist on the WMAP team, "is that the universe can be explained with five numbers." First, the cosmos is 13.7 billion years old, give or take a negligible couple of hundred million years. Second, the first stars turned on just 200 million years after the Big Bang. Finally, the universe is made of three things in the following proportions:4% ordinary atoms; 23% Jo "dark matter," whose nature is still unknown; and 73% "dark energy," the equally mysterious force whose antigravity effect is speeding up the cosmic expansion. "This," says astrophysicist John Bahcall, of the Institute for Advanced Study in Princeton, New Jersey, "is a rite of passage for cosmology, from speculation to precision science."
WMAP learned this and more by scrutinizing the faint whisper of microwaves left over from the Big Bang. Hidden in that radiation are patterns of warmer and cooler spots, marking places where matter was a little more or less dense than average spots that would eventually evolve into the clusters of galaxies and empty spaces that we see today. These patterns were first detected in crude form by the Cosmic Background Explorer satellite in 1992, but without enough detail for much to be said about them.
But with a resolution some 40 times as sharp as COBE’s, WMAP has plenty to say. "It’s a lot like matching fingerprints," says Spergel. "We ran computer simulations based on many different values for all of the numbers, generated patterns for each and found the one that best matched what we actually saw."
WMAP also confirmed what earlier experiments had suggested about a basic characteristic of the universe: the geometry of space-time, in the Einsteinian sense, is flat. That’s consistent with a theory called inflation, which posits that the cosmos underwent a period of turbocharged expansion before it was a second old. "I have to admit," says Bahcall, "that I was skeptical of the picture theorists had put together. Inflation, dark matter, dark energy—it’s all pretty implausible. But this implausible, crazy universe has now been confirmed with exquisite detail."
That’s not to say that WMAP has answered every question. Nobody knows what dark matter and dark energy are, and the theory of inflation, while strengthened, is far from proved. Beyond that, there are some strange measurements in WMAP’s data that might be mere statistical flukes—or might point to some major monkey wrench that could still throw cosmology into turmoil. "We should know better after we get in more data," says Charles Bennett of the Goddard Space Flight Venter, who is the V team leader.
But cosmologists won’t be sitting around waiting. "You’re going to see a thousand papers based on these results," says Tegmark, who is already working on several. "It’s an exciting time to be in this field.\
Which of the following statements is NOT true of the cosmos

A.Microwaves are the medium WMAP used to make measurements.
B.Warmer spots would finally develop into the clusters of galaxies.
C.Dark energy is a decisive factor in the cosmic expansion.
D.The nature of dark matter in space is unknown to scientists.
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问答题Today, science and technology develop very fast, and books on scientific and technological knowledge are published at a rate of almost unbelievable 60 million pages a year. Facing with such quantity of knowledge, as a modern individual, how can we deal with the knowledge explosion in order to catch up with the development of society Write an essay of about 400 words on the following topic: Coping with the Knowledge Explosion In the first part of your essay you should state clearly your main argument, and in the second part you should support your argument with appropriate details. In the last part you should bring what you have written to a natural conclusion or make a summary. Marks will be awarded for content, organization, grammar and appropriateness. Failure to follow the above instruction may result in a loss of marks.

Today, science and technology develop very fast, and books on scientific and technological knowledge are published at a rate of almost unbelievable 60 million pages a year. Facing with such quantity of knowledge, as a modern individual, how can we deal with the "knowledge explosion" in order to catch up with the development of society Write an essay of about 400 words on the following topic:
Coping with the Knowledge Explosion
In the first part of your essay you should state clearly your main argument, and in the second part you should support your argument with appropriate details. In the last part you should bring what you have written to a natural conclusion or make a summary.
Marks will be awarded for content, organization, grammar and appropriateness. Failure to follow the above instruction may result in a loss of marks.