1、大学英语六级-172 及答案解析(总分：100.00，做题时间：90 分钟)Fifty years ago, an American astronomer called Frank Drake started to search for signals coming from alien civilisations. Paul Davies, a British physicist, examines in a new book why it might be that mankind has not heard from extraterrestrials (外星生物), the signi
2、ficance of this lack of response, whether aliens might yet make contact and how people might react to them. The short answer is No one knows. The universe is immense, which makes many scientists confident that life might have evolved elsewhere. Perhaps, concedes Mr Davies, but for life to signal its
3、 existence, it must be intelligent, which whittles (缩减) things down a bit, and it must have developed science, which further slims the chances. Moreover, because the universe is so vast, it takes years for a signal travelling at the speed of light to reach only as far as the next star to our sun. Mo
4、dern man evolved as a species 100000 years ago but began broadcasting his existence less than 100 years ago. If mankind were, this week, to receive a reply from extraterrestrials that had tuned in to the earliest broadcasts, they must be living less than 50 light-years from the Earth. That is a tiny
5、 pocket in the universe. No surprise, then, that so far nothing has been heard. Mr Davies points out that scientists who search for aliens using radio telescopes are assuming that other life would use this form of communication. But people are increasingly using the internet to talk to one another.
6、Within the next 100 years, mankind may no longer use radio. Astronomers are using the only tools at their disposal but these may well be the wrong ones for the job. Of course, there is the possibility that intelligent, scientifically minded alien species do evolve quite readily on extrasolar planets
7、. This would be threatening for humanity, and is what makes the silence eerie. The lack of contact would suggest that intelligent life and technological civilizations may be inherently unstable, and destroy themselves before they can signal their existence to one another. Given the great size not on
8、ly of space but also of time, perhaps intelligent life looks different elsewhere. If mankind persists for a further 100000 years, the species will surely change. Indeed, it has already developed intelligent machines and is well on its way to building devices that are more intelligent than their make
9、rs.（分数：25.00）(1).What can we conclude from the first paragraph?（分数：5.00）A.People have got signals from alien civilizations.B.Aliens have already made contact with human beings.C.We are not certain about the existence of aliens.D.People have known how to react to aliens.(2).What does the word “conced
10、es“ (Para. 2) mean?（分数：5.00）A.To suggest friendly.B.To give away.C.To acknowledge reluctantly.D.To approve thoroughly.(3).What does the author think of using radio telescopes to search for aliens?（分数：5.00）A.He thinks it is a suitable way.B.He holds a neutral attitude towards it.C.He doesn“t think it
11、 is the right way.D.He believes it is better than using the Internet.(4).What do we know about aliens on extrasolar planets?（分数：5.00）A.They indeed exist on other planets.B.They have made contact with us.C.They may fight for space with us.D.They might be inherently unstable.(5).Which of the following
12、 is the topic of this passage?（分数：5.00）A.The existence of aliens.B.The threatening aliens.C.The aliens far away from us.D.The powerful aliens.Their eyes met across a crowded room. The party chatter ebbed away, and the music slowed. That first lovers“ gaze is the staple of the romantic novels, and sc
13、ientists believe they have now revealed the true nature of its attractive power. According to new research, romance has very little to do with it. “It does seem to be a sort of narcissistic (自恋的) thing. People are attracted to people who are attracted to them. It“s really a very basic effect that we
14、 are all, at some level at least, aware ofwhich is that if you smile at people and you maintain eye contact, it makes you more attractive,“ said Ben Jones in the Face Research Laboratory at the University of Aberdeen. He said the work challenges most previous studies of facial attractiveness that ha
15、ve focused on physical characteristics, such as a preference for symmetrical faces or masculine versus feminine features. “Social signals about how attracted someone else is to you actually seem to be quite important,“ he said. “You are attracted to people who are attracted to you, and that shows at
16、tractiveness is not about physical beauty.“ Dr Jones and his colleagues say they have shown that attraction is based on social cues that say, “I“m interested in you.“ The most important cue seems to be whether someone is looking directly at you. The team put together four different sets of digital i
17、mageswomen looking happy, women looking disgusted, men looking happy and men looking disgusted. In each case, the scientists made up pairs of images which were identical except that in one the person was looking directly at the camera and in the other their gaze was averted. Volunteers then rated th
18、e relative attractiveness of the images in each pair. The team found that a direct stare is attractive only if the person giving it looks as if they like you. This preference was even higher if the face in the picture was of the opposite sex. “What we found at the most basic level is that people lik
19、e faces with direct gaze more than they like the same faces with averted gaze,“ said Dr Jones. “In other words, people find themselves more attractive when they are being looked at.“ The results are published in the Proceedings of the Royal Society . Dr Jones said the results make sense from an evol
20、utionary perspective. “It takes quite a lot of effort to attract a mate and what you want to do is allocate that effort in a more efficient way, in other words, in a way that is more likely to help you secure a mate.“ So it seems there is no point wasting your time on someone who is just not interes
21、ted.（分数：25.00）(1).What do the romantic novelists often write about?（分数：5.00）A.The episode that lovers dislike each other at first sight.B.The place where lovers meet for the first time.C.Lovers“ first impressions of each other.D.The eye contact between lovers when they first meet.(2).What do previou
22、s studies say about attractiveness?（分数：5.00）A.Attractiveness is a sort of narcissistic thing.B.Attractiveness relies on physical beauty.C.Attractiveness relies on people“s relations.D.Attractiveness is based on social signals.(3).What can we know about social signals from Jones“ new discovery?（分数：5.
23、00）A.Smile is likely to make you more attractive.B.We are interested in people who have symmetrical faces.C.We are attracted to people who are interested in us.D.Attraction is based on physical characteristics.(4).According to the experiment of Jones“ team, we can reach a basic conclusion that _.（分数
24、：5.00）A.people who make direct eye contact with us are more attractive to usB.people who look depressed are more attractive than those who look happyC.people who look happy are more attractive than those who look depressedD.the opposite sex is more attractive than the same sex(5).Why did Dr Jones sa
25、y the results make sense from an evolutionary perspective?（分数：5.00）A.The results belong to the field of evolution.B.The results can help humans evolve faster.C.The results can help humans secure a better mate.D.The results match with the evolutionary need of finding a mate efficiently.Want to get so
26、me cash at automated teller machines in Nairobi? Don“t be surprised by the guards with machine guns. ATMs attract plenty of muggers and pickpockets. Unsurprisingly, cashless transactions have been catching on fast in Nairobi and elsewhere in Africa. Microfinance organizations were among the pioneers
27、. Musoni, a Kenyan microfinance firm with more than 10000 customers and over $6.3 million in loans since its launch in May 2010, is now taking the idea even further: In an effort to bypass banks and make microfinance more efficient, it has gone completely cashlessa worldwide first, claims Cameron Go
28、ldie-Scot, the firm“s chief operating officer. Cashless transactions are more secure: They are traceable and hard to redirect. Yet combining mobile money with brick-and-mortar banks adds costs. Using services such as M-PESA also does not do much to improve microfinance organizations. Most already en
29、joy high repayment rates, around 97% in some cases. Efficiency gains require a more radical approach. Hence Musoni“s going all digital. Its loan officers are armed with tablet computers and a custom application for collecting loan-applicant data. They take their devices to the field to check with ow
30、ners of portable toilets in Mukuru, a slum in Nairobi. These charge neighbours for a toilet“s use and sell the waste it collects to Sanergy, a partner of Musoni“s, which converts it into fertilizer and electricity. Loan officers estimate how many people live in a toilet“s vicinity to calculate the b
31、usiness“s future revenue. They also interview potential borrowers. All the data are stored in their tablets and on Musoni“s servers. And if the firm“s employees approve a loan, it will arrive by text messageas credit on the applicants“ M-PESA account. What is more, thanks to the tablets“ wireless co
32、nnection, loan officers can pull up a borrower“s payment history on the spot during weekly group meetings with other borrowers. And loan officers can activate automatic payment reminders, holiday greetings and marketing messages. All this allows them to cultivate relationships with a greater number
33、of borrowers than they could otherwise. Many other microfinance institutions also would like to go cashless, but they lack the necessary technology, says Mr Goldie-Scot. So Musoni will soon offer to license its system to other microfinance organizations for a fee. If it catches on, it will help brin
34、g down the cost of credit for many of the world“s 2.5 billion unbanked poor, explains Mr Goldie-Scot. For pickpockets, however, it would be bad news. Among some of them, cash is already out of fashion. They are now out to snatch mobile phones. In a crowded bar this correspondent batted intruding fin
35、gers away from the pocket containing his treasured mobile. In the crush a companion“s phone, alas, was stolen. In another pocket, though, your correspondent“s wallet sat untouched.（分数：25.00）(1).What contributes to the popularity of cashless transactions in Africa?（分数：5.00）A.The automated teller mach
36、ines are located in inconvenient places.B.Cash transactions in Africa are not secure.C.Cashless transactions have been a trend worldwide.D.The microfinance firms charge low fees for service.(2).What is said about the feature of cashless transactions?（分数：5.00）A.They are traceable and hard to redirect
37、.B.They can be perfectly combined with traditional banks.C.They cannot help microfinance organizations improve efficiency.D.They help improve the rate of repayment and profit.(3).How does Musoni improve its service?（分数：5.00）A.Each customer has been assigned a bank officer.B.The information and data
38、of customers are well preserved.C.It moves its offices to locations near the working field.D.The loan officers take portable computers when they work at their customers“ places.(4).What do Musoni“s loan officers provide for their customers?（分数：5.00）A.They help the customers calculate their expected
39、earnings.B.They use text messages to inform the customers of their credit history.C.They remind the customers to make payments on time.D.They put their customers into a mature network of relationships.(5).What is cashless payment likely to bring to Nairobi?（分数：5.00）A.The enthusiasm for developing th
40、e technology.B.The improvement in the living standards of the poor.C.The change in the targets for the local pickpockets.D.The popularity of multifunctional mobile phones.Fossil hunters have unearthed fragments of leg bone belonging to a giant camel that lived in the forests of the High Arctic more
41、than three million years ago. The ancient beast stood almost three meters tall at the hump, about a third higher than its modern descendant, the single-humped dromedary (单峰驼), or Arabian camel. Scientists who found the remains said the extinct mammal may have already had the wide, flat feet and fatt
42、y hump associated with adaptation to life in the desert, because they could have helped the animal endure its harsh, snow- covered habitat. Remnants of the oversized ungulate (有蹄类动物), 30 pieces in all, were recovered from a steep, sandy slope on Ellesmere island, the most northern and mountainous of
43、 the Canadian Arctic archipelago (群岛). The sediments around the fossils date to at least 3.4 million years old, when the region was much warmer than today and dominated by larch (落叶松) forests. Temperatures hovered a few degrees below zero, and winters plunged the region into six months of darkness.
44、Fossils from previous expeditions have shown that the camel“s ancestors originated in North America 45 million years ago, and crossed the Bering Strait into China and Eurasia more than 7 million years ago. In 1913, the first giant camel remains were uncovered in Yukon, about 1200km south of the Fyle
45、s Leaf Bed. “This is the first evidence of camels in the High Arctic,“ said Mike Buckley, a researcher at Manchester University who studied the remains. The frigid conditions on Ellesmere island preserved connective tissue called collagen (胶原蛋白) in the specimens. When Buckley compared the chemical m
46、akeup of the collagen with tissue from the Yukon camels, he found they were closely related, and possibly the same species. They also matched modern dromedaries, but not the twin-humped Bactrian camel. The study appears in the journal, Nature Communications . “This ancestor of modern camels may alre
47、ady have had some of the adaptations that helped it survive in harsh climatesthe hump for fat storage for instance. The large flat feet were ideal for soft ground, so it didn“t sink through sand or snow. The large eyes perhaps helped with poor visibility in the long, dark winters,“ said Buckley. No
48、other mammal remains have been unearthed at Fyles Leaf Bed, but at a nearby site, expeditions uncovered fossilized remnants from a beaver, a three-toed horse and a badger, that lived at the same time. “We now have a new fossil record to better understand camel evolution,“ said Natalia Rybczynski, at
49、 the Canadian Museum of Nature in Ontario. “Perhaps some specializations seen in modern camels, such as their wide flat feet, large eyes and humps for fat may be adaptations derived from living in a polar environment.“（分数：25.00）(1).What do we know about the features of the ancient giant camel?（分数：5.00）A.It had big and fatty feet.B.It was similar to its modern descendent in size.C.It was well adapted to the harsh conditions.D.It had wide feet suitable to walk on mud.(2).What is said about the environment that the ancient camel lived in?（分数：5.00）A.The region was full of steep and sandy
