题目内容
下面哪一条成立时,称X→Y为平凡的函数依赖？
查看答案
搜索结果不匹配？点我反馈
更多问题
These marshes are the breeding ground for snow geese. Once destroyed, some fear the species will take over the habitat of the Canada goose —a popular game bird in Minnesota. If this happens, Minnesota hunting and land conditions could be greatly affected.
The snow goose population has been on the rise in the last 25 years, but numbers are hitting an all-time high. This year there is an estimated 4.5 or 6 million birds, triple what the population was 25 years ago.
Although effects of the snow goose invasion aren't apparent in Minneapolis, northern Minnesota and Canada can clearly see the signs. The population growth is due to the birds' wintering habits. They fly south to Louisiana, Texas and Mississippi to nest. The conditions and food availability there have made it possible for more birds to survive the winter and make the trip back north. The period over which they've increased in number correlates to a change in agriculture practices in the region.
After World War Ⅱ, there was an increase in man-made fertilizers, yielding an increase of corn, rice, wheat and other crops. "There have also been other changes in agricultural practices causing an increase of production in cereal crops.
The geese find the agricultural areas better than the natural areas. The geese have escaped from any natural limits. They are not doing this on their own, it is in response to human practices.
Usually, about 70 to 75 percent of the birds make it back to Canada in late winter and early spring. But the surviving number of snow geese has steadily climbed each year to reach 95 percent in the last couple of years. Because so many survive, they strip the capacity of the breeding ground.
The snow geese are destroying salt marshes where they nest in the summer, about 30 percent of the salt marshes are completely destroyed, leaving them as inhabitable mud flats. Another 35 percent of salt marshes are significantly damaged.
There are three possible solutions: Let the problem take care of itself and wait for the population to crash, deal directly with the population by changing hunting limits and regulations or address the cause of the problem in the south.
According to the author, if the northern marshes are destroyed,______.
SECTION B INTERVIEW
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Questions 1 to 5 are based on an interview. At the end of the interview you will be given 10 seconds to answer each of the following five questions.
Now listen to the interview.
听力原文：Policeman: Now, sir, I'm sorry to have kept you waiting. I had to look after the traffic on the road until some more police arrived. You're the driver of the blue ear, I believe.
Mr Simpson: Yes.
Policeman: Just a few questions, sir. Do you feel all right？
Mr Simpson: Yes, I'm...I'm fine now. I was a little shaken up at first.
Policeman: Well, I'll try not to keep you long. I just want a few details, and the rest of the information I can get tomorrow. Can I have your name and address, please？
Mr Simpson: Jeremiah Simpson, 15 Portland Crescent, Leeds.
Policeman: Have you got your driving license and insurance certificate with you？
Mr Simpson: Yes... Oh, here they are.
Policeman: M' Inn... Thank you... Oh... Yes, they're all right. Now, were there any passengers in the car？
Mr Simpson: Er yes, er my wife and a friend -- a young lady. My wife was sitting in the back and her friend in the front passenger seat.
Policeman: Where are they now？
Mr Simpson: The ambulance has just taken them to hospital. You spoke to the ambulance driver before he set off. Did he say anything about the young lady？
Policeman: He said that her injuries looked worse than they really were. The other woman --- that'd be your wife, I assume -- appeared to be suffering from shock.
Mr Simpson: Yes, I know. They advised her to go to hospital for a check-up, just in case...
Policeman: Mm. Was the young lady wearing her seat-belt？
Me Simpson: No, unfortunately. I told her to put it on, but she couldn't adjust it. I didn't think it was worth stopping the car because we were only going a few miles.
Policeman: Did she go through the windscreen？
Mr Simpson: No, she was very lucky. But she hurt her leg on the dashboard.
Policeman: Mm. It could've been much worse. Now, sir, will you tell me in your own words what happened？
Mr Simpson: Oh... Well, as you can see, I was travelling along this main road when suddenly er the other car came out of er that side street. It all happened so quickly. I just didn't see him until he hit me.
Policeman: I've just spoken to the other motorist and he says that you were speeding.
Mr Simpson: What？
Policeman: Is this true？
Mr Simpson: That's a lie. My wife and Becky'll tell you that I stopped at the pedestrian crossing just down them. You can see it's only fifty yards away. I could hardly have reached thirty miles an hour by the time I got here. Goodness knows what would've happened if I'd been going faster.
Policeman: The other driver said that he stopped at the junction. When he pulled out there was nobody coming, so you must at the junction. When he pulled out there was nobody coming, so your must have been speeding.
Mr Simpson: Well, it's not true. I've witnesses to prove it. He couldn't have stopped. The lighting is very good here along this stretch.
Policeman: Yes. He should have stopped. Why did you stop at the pedestrian crossing？
Mr Simpson: There were two old ladies on it. I'm always a bit careful with old people because they're likely to walk across the road without looking properly.
Policeman: I shouldn't worry, sir. We don' t think you were speeding -- even without measuring the skid marks.
Mr Simpson: Er, was he -- er, the other driver -- drunk？
Policeman: I don't know yet. He's admitted that he's had one or two drinks, but says it was only two half-pints. We're going to give him a breathalyser test to see whether he's over the limit. If he is, he'll be asked to have a blood test.
Mr Simpson: Well, I haven't touched a drop all night!
Policeman: No, sir. It's surprising how much a driver's b
The earliest films were short, lasting only one minute or less. People could, for one cent, see simple action films of trains, fire engines, parades, crowds on city streets and similar subjects. Soon 20-minute pictures of news items were being shown in theaters at the end of the regular stage show. Later, films used a new method (putting the beginning of one scene upon the end of the scene before)for magical effects and to tie a story together. In 1903, a film was made about a train robbery, much of the action took place at the same time —— the robbers escaping, the men meeting and planning to capture them -- and the scenes moved smoothly, back and forth, from one scene to another instead of unnaturally showing each scene separately. This was the earliest successful film in which scenes were filmed at different places and times and then combined to make a logical story. A short time later, theaters showed for five cents a whole hour's entertainment of short films -- comedy, travel, and dramas. These films were simple and rough, and many were vulgar. Gradually the tastes of the audiences improved as the techniques improved.
Before 1910 actors were employed in films without their names being given because the producers were afraid that if an actor became well known, he might demand more money. But later, it became known that a film with a popular actor in it could be sold at a higher price to theater owners than a film in which the actor was not known. Soon "movie stars" won fame wherever films were shown. By 1915, the most popular stars were earning as much as $ 2, 000 a week, and large theaters were being built downtown in all the larger cities to show films alone. The films shown in those theaters were of several types: comedies emphasizing speed, movement and camera tricks; serious dramas, often with a patriotic theme; "westerns", which showed, then as now, the American cowboy fighting on the side of law and justice; murder mysteries and crime stories, and special films on art, music and other cultural subjects.
Pictures of parades shown in the first films went on for no more than ____.
Part A
Directions: Read the following three texts. Answer the questions on each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.
Live theatre lives. In England in every town, someone is rehearsing, someone devising, some-one performing. Winchester is a good example. Ancient capital of England, population approximately 60, 000 when you take in the suburbs. Live theatre comes to Winchester and made in Winchester, week in week out.
It has a 400-seat theatre in the city centre and an arts centre in the outskirts seating 150. These offer a programme of visiting compaies on a tour of one-night or three-to-four night stands, moving from one gathering place to another around the country, using moveable sets in flexible space. New productions of classic works, ancient and modern but always live: each performance different because it's a different audience in a different town. The tour usually lasts the company two or three months before it's time to settle down to devise and rehearse the next one.
For the performer, touring is a chance to work with the same people in the security of a company unit. But it' s also a chance to try something different night: to find out what works by actually doing it. And it doesn't always work. So what if it flops？ You are on the road and perform. it again in another place tomorrow. The audience will have forgotten by the time you come around again next year.
Each company's different, each has its own style, and audiences get to know them. But Winchester also has its own fringe (边缘) theatre 200 yards or so from the cathedral. This is where live theatre is conceived. The North Pole, it seats 50 to 60 people. Here it' s new work, amateur and semi-professional work, sometimes slick (熟练的), sometimes rough and ready. At least a dozen world premieres (首次公演)a year: many of them short-lived, quickly forgotten, some of them best forgotten, but all of them performed in excitement and expectation, neither audience nor performer quite knowing what' s going to happen. But one or two shows stick in the mind, some return reworked a year or so later the better for being polished on the live stage, some will work their way out of Winchester onto the touring circuit. Someone somewhere is always thinking of starting a company.
Which of the following is not true of Winchester？
微信支付 
支付宝支付