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Scientists at Royal Holloway, University of London  and Queen Mary, University of London have discovered that bees learn to fly the shortest possible route between flowers even if they discover the flowers in a different order. Bees are effectively solving the “traveling salesman problem”, and they are the first creatures found to do this.

The traveling salesman must find the shortest route that allows him to visit all locations on his route. Computers solve it by comparing the length of all possible routes and choosing the shortest, and it can keep computers busy for days. However, bees solve it without computer assistance using a brain the size of grass seed. Dr. Nigel Raine, from the School of Biological Sciences at Royal Holloway explains, “Bees solve traveling salesman problems every day. They visit flowers at multiple locations and because bees use lots of energy to fly, they find a route which keeps flying to a minimum. ”
The team used the computer to control artificial flowers to test whether bees would follow a route defined by the order in which they discovered the flowers or if they would find the shortest route. After exploring the location of the flowers, bees quickly learned to fly the shortest route.
As well as improving our understanding of how bees move around the landscape pollinating(授粉)crops and wild flowers, this research, which is due to be published in The American Naturalist, has other applications. Our lifestyle relies on networks such as traffic on the roads, information flow on the Web and business supply chains. By understanding how bees can solve their problems with such a tiny brain, we can improve our management of these everyday networks without needing lots of computer time. Dr. Raine adds, “Despite their tiny brains, bees are capable of extraordinary feats of behavior. We need to understand how they can solve the traveling salesman problem without a computer. ”
What would be the best title of the passage?

A.Bees help salesmen travel
B.Tiny-brained bees solve a complex mathematical problem
C.How bees discover the flowers
D.How to solve the “traveling salesman problem”

We may infer from the second paragraph that the “traveling salesman problem”    .

A.can be solved by a computer easily
B.can’t even be solved by a computer
C.can puzzle both people and computers
D.remains to be solved by scientists

The main purpose of the last paragraph is to   .

A.provide further proof for the research
B.tell us how bees can fly the shortest route between flowers
C.tell us how the research about bees’ flying route was conducted
D.explain the importance of the research

It can be concluded from the passage that   .

A.all creatures are smarter than computers
B.the research about bees’ flying route can be applied to many fields
C.our networks are more complex than bees’ ones
D.with the help of the computer we can find out how bees can solve the “traveling salesman problem”
科目 英语   题型 阅读理解   难度 中等
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相关试题

第三部分:阅读理解(共20小题;每小题2分,满分40分)
阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。
A
When I was sixteen years old, I made my first visit to the United States. It wasn’t the first time I had been abroad. Like most English children, I learned French at school. I had often been to France, so I was used to speaking a foreign language to people who didn’t understand French. But when I went to America, I was really looking forward to having a nice and easy holiday without any language problems.
How wrong I was! The misunderstandings began at the airport. I was looking for a public telephone to give my American friend Daisy a call and tell her that I had arrived. A friendly old man saw me looking lost and asked if he could help me.
"Yes, "I said, "I want to give my friend a ring. "
"Well, that's nice, "he said. "Are you getting married? But aren't you a bit young?"
"Who is talking about marriage?" I replied. "I only want to give my friend a ring to tell her I've arrived. Can you tell me where there's a phone box?"
"Oh! "he said. "There's a phone downstairs. "
When at last we met, Daisy explained the misunderstanding to me.
"Don't worry, "she said to me. "I had so many difficulties at first. There are lots of words which the Americans use differently in meaning from the British. You' ll soon get used to all the funny things they say. Most of the time, British and American people understand each other!"
56. The writer thought ______ in America.
A. he wouldn't have any language difficulties
B. he would not understand the Americans
C. the Americans might not understand him
D. he would have difficulty at the airport
57. The writer wanted to _____.
A. buy a ring for his friend
B. make a call to his friend
C. go to the telephone company
D. see his friend off
58. From the passage we can see that "give somebody a ring" ______.
A .means the same in America as in England
B. means "call somebody" to the old man
C. has two different meanings
D. means "be going to get married" in England
59. In the last paragraph the underlined word "they" refers to ______.
A. the old man and the boy B. the Americans
C. the British D. the French

C
Elizabeth Blackwell was born in England in 1821, and moved to New York City when she was ten years old. One day she decided that she wanted to become a doctor. That was nearly impossible for a woman in the middle of the nineteenth century. After writing many letters asking for admission(录取) to medical schools, she was finally accepted by a doctor in Philadelphia. She was so determined that she taught school and gave music lessons to get money for the cost of schooling.
In 1849, after graduation from medical school. she decided to further her education in Paris. She wanted to be a surgeon(外科医师) , but a serious eye problem forced her to give up the idea.
Upon returning to the United States, she found it difficult to start her own practice because she was a woman. By 1857 Elizabeth and her sister, also a doctor, along with another woman doctor, managed to open a new hospital, the first for women and children Besides being the first woman physician and founding her own hospital , she also set up the first medical school for women.
66. Why couldn’t Elizabeth Blackwell realize her dream of becoming a surgeon?
A. She couldn’t get admitted to medical school
B. She decided to further her education in Paris
C. A serious eye problem stopped her
D. It was difficult for her to start a practice in the United States
67. What main obstacle(障碍) almost destroyed Elizabeth’s chances for becoming for a doctor?
A. She was a woman.
B. She wrote too many letters.
C. She couldn’t graduate from medical school.
D. She couldn’t set up her hospital.
68. How many years passed between her graduation from medical school and the opening of her hospital?
A. Eight years B. Ten yearsC. Nineteen yearsD. Thirty-six years
69. According to the passage, all of the following are “firsts” in the life of Elizabeth Blacekwell except that she ______.
A. became the first woman physician
B. was the first woman doctor
C. and several other women founded the first hospital for women and children
D. set up the first medical school for women
70. Eilzabeth Blackwell spent most of her lift in _______.
A. England B. Paris C. the United States D. New York City

B
A young British sailor was missing at sea yesterday in similar circumstances(情况)to the way his father died five years ago.
The dinghy(救生橡皮船),used to take Richard Smith,21,to his yacht(快艇),was discovered empty, floating in seas off the Caribbean island.An air and sea search was carried out but he has still not been discovered.
Richard’s mother, Bicknell,said from her home in Hampshire,“It’s so much coincidence.Richard always carried a photograph of his father attached to a poem,which included the date of his disappearance.”
“Now, it’s very strange because all they have found is Richard’s dinghy.We need to know this time what has happened one way or another.If you know at least you can go through the grieving process(悲痛的过程).”
In November 1996,Mr. Smith’s father, Charlie,was sailing in the Tasmen sea between the Australian mainland and the island of Tasmen with his new wife.They lost radio contact with the shore and they, together with their yacht were never seen again,and their disappearance remains a mystery.
Richard is described a talented(有才能的)and experienced sailor who has crewed for the champion ocean racer.He had sailed to the。Caribbean in November to crew ocean racing yachts for entertainment.He ended the evening drinking in the Abracbabra bar but left after local police closed it for being too noisy.
About 2 am the following day Richard headed back for his dinghy.He started its outboard motor before giving all elderly woman a lift to her yacht after her dinghy had gone missing.It was the last time he was seen.
61.Riehard Smith was___________in 2000.
A.ten B.fifteen C.twenty D.eighteen
62.People searched for Richard using_____.
A.ship only B.ship and radio C.ship and plane D.yacht and car
63.According to the passage,we know Richard died because____.
A.he was a green hand in sailing
B.some unknown animal attacked him
C.that was a maze in the area he was sailing
D.of something we don’t know
64.Which statement is NOT true according to this passage?
A.Young Smith had lost radio contact with the shore before he died.
B.Richard’s father had married two women at least.
C.Richard didn’t drink on the evening before he was lost because the policeman closed the bar.
D.Richard was seen at about 2 am the day he disappeared.
65.The writer tells us__________.
A.a story about two heroes B.a piece of news about a merchant ship
C.a coincidence D.the dying process of Richard

第三部分:阅读理解(共15小题;每小题2分,满分30分)
阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出一个最佳选项。
A
Satellites are an important part of our ordinary lives.For example, the information for weather forecasts is sent by satellite.Some satellites have cameras which take photographs of the Earth to show how clouds are moving.Satellites are also used to connect our international phone calls.
Computer connections of the World Wide Web and Internet also use satellites. Many of our TV programs come to US through satellites.Airplane pilots also sometimes use a satellite to help them find their exact location.
We use satellites to send television pictures from one part of the world to another.They are usually 35,880 kilometers above the equator.Sometimes we can see a satellite in the sky and it seems to stay in the same place.This is because it is moving around the world at 11,000 kilometers an hour—exactly the same speed that the earth rotates.A satellite must orbit the Earth with its antennae(天线)facing the earth.Sometimes, it moves away from its orbit,So there are little rockets on it which are used to put the satellite back in the right position.This usually happens about every five or six days.
Space is not empty! Every week, more and more satellites are sent into space to orbit the Earth.A satellite usually works for about 10-12 years.Satellites which are broken are sometimes repaired by astronauts or sometimes brought back to Earth to be repaired.Often,very old or broken satellites are left in space to orbit the Earth for a very long time.This is very serious because some satellites use nuclear power and they can crash into each other.
56.Which of the following is NOT done by satellites according to the passage?
A.Sending information for weather forecast.
B.Taking photographs of the Earth.
C.Sending TV pictures.
D.Providing food for airplane pilots.
57.What’s the speed the earth rotates at?
A.35,880 kilometers per hour. B.335,880 kilometers per hour.
C.11,000 kilometers per hour. D.110,000 kilometers per hour
58.Why does the satellite move around the world at the same speed as the Earth rotates?
A.In order to take photographs.
B.In order to stay in a certain position in the orbit.
C.In order to move away from its orbit.
D.In order to send television pictures.
59.What does the underlined word “This” refer to?
A.A satellite.
B.A little rocket.
C.A satellite seems to stay in the same place in the sky.
D.The satellite puts the rockets in the right position.
60.Which is true of satellites?
A.A satellite usually works for about 10-2 years.
B.Every time a satellite gets broken,it is brought back to the Earth to be repaired.
C.A broken satellite is never left in space.
D.They often crash into each other.

D
Lex Kim English School Information Session Description
Lex Kim English School offers language improvement courses in reading, writing, grammar, and speech to students from Grades 3 to 11. All classes are conducted in English and class sizes are no larger than 10 students.
We are looking for full-time teachers and assistant teachers who’re interested in very organized self-starters. Our application process includes a phone interview, an in-person interview, and a sample teaching period. Additionally, all applicants must standards for the available positions:
Native English speakers with at least 15 years’ experience in teaching
A Bachelor’s degree or higher (preferably in education, English, or related fields)
Benefits
Teacher pay ranges from $26,000 to $45,000 depending on experience plus overtime pay and various performance-based prizes throughout the year free dinners, and other benefits.
Required documents:
The cover letter ( please indicate the position you are applying for )
The resume(个人简历)with your Date The recent photo of yourself or the copy of your passport
At least two references(推荐信)from your former employer
Contact
Please visit our website at www.lexkimjob.com for more information and visit http://lexkimjob.com/apply/main.php to submit(提交)your application.
53. According to the passage, Lex Kim English School _______.
A. only offers classes to the students in the morning
B. has students of all ages who are weak in English
C. is very strict about the application process
D. is badly in need of part-time English teachers
54. Who is the most likely to be hired by Lex Kim English School ?
A. A Frenchman with a Bachelor’s degree in education
B. An American with a Master’s degree in economics
C. A Korean with a Doctor’s degree who has worked in America for 18 years
D. An Englishman who has 16 years’ experience in teaching in a Canadian college
55. We can know from the passage that _______.
A. applicants must hand in their passports to the school
B. teachers of Lex Kim English School must use English to teach grammar
C. the more experienced applicants are, the higher pay they will get
D. applicants can go directly to the school to apply for the positions

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