题目内容
根据材料请回答 16～22 题
Fermi Problem
On a Monday morning in July, the world' s first atom bomb exploded in the New
Mexico desert.Forty seconds later, the shock waves reached the base camp where the I-talian-American physicist Enrico Fermi and his team stood.After a mental calculation, Fermi announced to his team that the bomb's energy had equated 10,000 tons of TNT.The bomb team was impressed, but not surprised.Fermi' s genius was known throughout the scientific world.In 1938 he had won a Nobel Prize.Four years later he produced the first nuclear chain reaction, leading' us into the nuclear age.Since Fermi's death in 1954,no physicist has been at once a master experimentalist (实验家) and a leading theoretician
Like all virtuosos (大师), Fermi had a distinctive style.He preferred the, most direct route to an answer.He was very good at dividing difficult problems into small, managea-ble bits talent we all can use in our daily lives,
To develop this talent in his students, Fermi would suggest a type of question now known as a Fermi problem.Upon first hearing one of these, you haven't the remotest no-tion of the answer, and you feel certain that too little information had been given to solve it.Yet when the problem is broken into sub-problems， each answerable without the help of experts or books, you can come close to the exact solution.
Suppose you want to determine Earth's circumference without looking it up.Every-one knows that New York and Los Angeles are about 3,000 miles apart and that the time difference between them is three hours.Three hours is one-eighth of a day, and a day is the time it takes the planet to complete one rotation (旋转), so its circumference must be eight times 3000 or 24000 miles.This answer differs from the true value, 24,902.45 mi-les, by less than four percent.
Ultimately (最终地) the value of dealing with everyday problems the way Fermi did lies in the rewards of making independent discoveries and inventions.It doesn't matter whether the discovery is as important as determining the power of an atom or as small as measuring the distance between New York and Los Angeles.Looking up the answer, or letting someone else find it, deprives you of the pleasure and pride that accompany creativ-ity, and deprives you of an experience that builds up self-confidence.Thus, approaching personal dilemmas as Fermi problems can become a habit that enriches your life.
第 16 题 Fermi's team was impressed by Fermi' s announcement in the base camp because he could even work out the power of the atom bomb in his mind.
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根据材料请回答 16～22
Will We Take Vacation in Spaces？
When Mike Kelly first set out to build his own private space-ferry service, he figured his bread-and-butter business would be lofting(发射) satellites into high--Earth orbit(轨道).Now he thinks he may have figured wrong."People were always asking me when they could go," says Kelly, who runs Kelly Space & Technology out of San Bernardino, California."I realized that real market is in space tourism."According to preliminary market surveys, there are 10,000 would-be-space-tourists willing to spend $1 million each to visit the final frontier.Space Adventure in Arlington, Virginia, has taken more than 130 deposits for a two-hour, $98,000 space tour tentatively (and some- what dubiously(可疑地) set to occur by 2005.Gene Meyers of the Space Island Group says: "Space is the next exotic(风光奇特的) vacation spot." This may all sound great, but there are a few hurdles(困难).Putting a simple satel- lite into orbit with no oxygen, life support or return trip necessary already costs an astro- nomical(天文数字的) $22,000/kg.And that doesn't t include the cost of insuring rich and possibly litigious passenger.John Pike of the Federation of American Scientists acerbically(尖刻地) suggests that the entire group of entrepreneurs trying to corner(垄断)the space-tourism market have between them "just enough money to blow up one rocket.” The U.S.space agency has plenty of money but zero interest in making space less expensive for the little guys.So the little guys are racing to do what the government has fainted to do: design a reusable launch system that is inexpensive, safe and reliable.Kelly Space's prototype looks like a plane that has sprouted rocket engines.Rotary Rocket in Redwood City, Cali- fornia, has a booster with rotors to make a helicopter-style. return to Earth; Kistler Aero- space in Kirkland, Washington, is piecing together its versions from old Soviet engines, shuttle-style. thermal protection tiles and an elaborate parachute system.The first passen-ger countdowns are still years away, but bureaucrats at the Federal Aviation Administra- tion in Washington are already informally discussing flight regulations.After all, you can't be too prepared for a trip to that galaxy far, far away.
For those who are intent on joining the 100-mile high club, Hilton, and, Budget are plotting to build space hotels.Before the Russian spaceship Mir came down, some people were talking about using it as a low-rent space hotel to reduce the cost.If a space hotel is finally built in space, and if you are thinking of staying in it, you may want to check the Michelin ratings before booking yourself a suite.
第 16 题 Mike Kelly planned to turn his business of making bread and butter into a busi-ness that is engaged in space tourism.
根据材料请回答 31～35 题
Dr Thomas Starzl, like all the pioneers of organ transplant, had tO live with failure.When he performed the world's first liver transplant 25 years ago, the patient, a three-year-old boy, died on the operating table.The next four patients did not live long enough to get out of the hospital.But more determined, than discouraged, Starzl and his colleagues went back to their lab at the University of Colorado Medical School.They devised(发明)techniques to reduce the heavy bleeding during surgery, and they worked on better ways to prevent the recipient' s immune system(免疫系统) from rejecting the organ- an ever-present risk.Now, thanks to further refinements, about two thirds of all liver-transplant patients are living more than a year.
But the triumphs of the transplant surgeons have created another tragic problem: a severe shortage of donor organs."More and more people go on the waiting lists and there is wide disparity(差异)between supply and need," says one doctor.The American Council on Transplantation estimates that on any given day 15,000 Americans are waiting for or-gans.There is no shortage of actual organs; each year about 25,000 healthy people die un-expectedly in the United States, usually in accidents.The problem is that fewer than 20% become donors.
This trend persists despite laws designed to encourage organ recycling.Under the federal Anatomical Gift Act, a person can authorize the use of his organs after death by signing a statement.Legally, the next of kin can veto(否决)these posthumous(死后的)gifts, but surveys indicate that 70% to 80% of the public would not interfere with a family member's decision.The bigger roadblock, according to some experts, is that physicians do not ask for donations, either because they fear offending grieving survivors or because they still regard some transplant procedures as experimental.
When there are not enough organs to go around, distributing the available ones be-comes a matter of deciding who will live and who will die.Once donors and potential recip-ients have been matched for body size and blood type, the sickest patients customarily go to the top of the local waiting list.Besides the seriousness of the patient's condition, doc-tors base their choice on such criteria as the length of time the patient has been waiting and how long it will take to obtain an organ.
第 31 题 Which of the following statements is true according to the passage？
A．permittedB．knewC．suspectedD．held
The word "message" in the last paragraph means__________.
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