To a culture which has come to take instantaneous communication for granted, as part of the very structure of civilized life, this “time barrier” may have a profound psychological impact. It will be a perpetual reminder of universal laws and limitations against which not all our technology can ever prevail. For it seems as certain as anything can be that no signal-still less any material object-can ever travel faster than light.
The velocity of light is the ultimate speed limit, being part of the very structure of space and time. Within the narrow confines of the solar system, it will not handicap us too severely. At the worst, these will amount to twenty hours-the time it takes a radio signal to span the orbit of Pluto, the outer-most planet.
It is when we move out beyond the confines of the solar system that we come face to face with an altogether new order of cosmic reality. Even today, many otherwise educated men-like those savages who can count to three but lump together all numbers beyond four-cannot grasp the profound distinction between solar and stellar space. The first is the space enclosing our neighbouring worlds, the planets; the second is that which embraces those distant suns, the stars, and it is literally millions of times greater. There is no such abrupt change of scale in the terrestrial affairs.
Many conservative scientists, appalled by there cosmic gulfs, have denied that they can ever be crossed. Some people never learn; those who sixty years ago scoffed at the possibility of flight, and ten years ago laughed at the idea of travel to the planets, are now quite sure that the stars will always be beyond our reach. And again they are wrong, for they have failed to grasp the great lesson of our age-that if something is possible in theory, and no fundamental scientific laws oppose its realization, then sooner or later it will be achieved.
On day we shall discover a really efficient means of propelling our space vehicles. Every technical device is always developed to its limit and the ultimate speed for spaceships is the velocity of light. They will never reach that goal, but they will get very near it. And then the nearest star will be less than five years’ voyaging from the earth.
1. For light to travel across the solar system, it will take
A a year
B nearly a day
C two months
D thirty minutes
2. The fact that it will never to be possible to converse with someone on another planet shows that
A radio messages do not travel fast enough
B no object can ever travel faster than light
C western culture has a special idea of communication
D certain universal laws cannot be prevailed against
3. Confronted with the new order of cosmic reality, many educated men
A become ignorant savages again
B find the “time barrier” unbearable
C will not combine solar and stellar space
D cannot adapt to the abrupt change of scale
4. Conservative scientists who deny that cosmic gulfs can ever be crossed will
A laugh at the very idea of flight
B learn a lesson as they did ten years ago
C find space travel beyond their reach
D oppose the fundamental scientific laws
5. The author of the passage, readers an infer, intends to show the
A limitations of our technology
B vastness of the cosmic reality
C prospect of planetary travel
D psychological impact of time and space
Unit 12
Directions
Read the following text Answer the questions below each text by choosing A,B,C or D. Mark your answer on ANSWER SHEET 1 (40 points)
Text 1
Many of world’s big lakes are threatened by pollution or huge drainage schemes. But there is at least one fairly bright spot. The Great Lake and St. Lawrence river system between Canada and the united states, which together account for a fifth of the world’s non-polar fresh water, are much healthier than they were. Can they stay that way
Though Lake Michigan is wholly the United States, all five lakes are governed by the Boundary Waters Treaty of 1909, implemented by an independent bi-national joint commission. In 1978, both countries agreed to try to clean up the water in the lakes, several of which were heavily polluted. They have done so-though in fact the improvement owes as much to economic change as to government action. Steel and other heavy industry have given way to cleaner industries and services, both in Ontario and in American lakeside states. The result tests on fish and birds show residues of heavy metals have declined (though dangerous levels of mercury are still found), while in the past ten years the rivers near Toronto have been successfully stocked with salmon.
There are still worries. One problem is farming. This uses much lake water(29% of the total that is withdrawn) fro irrigation, while also polluting the lakes and river system. The huge quantities of manure spread on farms in Ontario and Quebec also causes pollution, by running off the land into streams, rivers and then lakes.
Some scientists also worry that water levels will fall permanently. Climate change is likely to cut rainfall in the Great Lakes basin, while ever more water will be drawn from the lakes by a rising urban population. General consumption in the basin will increase by 25% in the next 25 years, according to a forecast by a consultant to the commission.
Other threats include some 140 exotic species of flora, fish and shellfish that have found their way in to the lakes, some via ships’ ballast, the zebra mussel from Eastern Europe is the most notorious and probably most damaging to the environment. It consumes a lot of oxygen (though is also helps to clean the water). Lastly, there is the hazardous prospect of decommissioning Ontario’s two dozen ageing nuclear reactors, which line the shores of Lake Ontario and Lake Huron.
Fortunately, the lone history of successful co-operation between the two countries and among the local governments suggests these threats can be managed. Both governments have approved the commission’s plan to set up international watershed boards across the continent. These are to take a “holistic” approach to ecosystems. Maybe the Zebra mussel and the farm run-offs have met their match.
1.from the text, we know that the Great Lakes
A are equally located between Canada and the US
B contain a small part of the world’s fresh water.
C are governed neither by Canada nor by the US
D enjoy fresher water now than 25 years ago
2. in the first two paragraphs, the author suggests
A the bi-national joint commission has done its routine job
B the Boundary Water Treaty of 1909 has become out-of-date
C the huge drainage schemes are to blame for land run-offs
D the economic change has contributed to environmental improvement
3. which of the following shows that water quality has improved
A fish and birds show residues of heavy metal.
B Toronto has grown salmon successful in its waters.
C farming has prospered in the lakeside areas.
D lake water has been drawn for use by the population.
4. which of the following causes concerns of the public and the scientists
A fish farming.
B urban population.
C Decreased rainfall.
D more landslide.
5. what is the author’s attitude to the prospect of the lakes’ environment
A optimistic.
B worried.
C indifferent
D unclear
Text 2
It is called softwood, but these days it’s producing nothing but hard feelings. Softwood is used to build houses, stuff that in skilled hands changes from a pile of wood in to a recognizable home in mere days. In the US, about 30% of such softwood comes from Canada. But on March 22nd the Department of Commerce announced that it would slap a tariff of around 29% on Canadian softwood. The Americans contend that Canada is subsidizing its timber industry, and dumping wood on to its neighbour for sale at prices that do not cover its production cost.
The Canadian hotly deny this, and the two sides are volleying expertise at each other. “They’ve hired their experts, and we’ve hired ours,” says John Allan, president of the British Columbia Lumber Trade Council.
In Canada the provincial governments own forests, and each province is given considerable freedom in pricing its “stumpage”, as standing trees are oddly called. American critics say the Canadians all but give away those uncut trees. John Perez-Garcia, a professor of forestry at the University of Washington in Seattle, estimates that Canadian logging companies pay as much as 60% less for standing trees than they would if the market set the prices.
Not so, retort the Canadians. Dan Evans, managers of log exports for British Columbia’s government, points out that stumpage fees cover only a small portion of what it cost a Canadian company to send lumber across the border. These companies, he says, have to build their own roads, re-forest logged land, and pay the cost of planning their sales. “We feel we price our timber competitively.” It is worth noting that for years American companies were themselves accused of receiving subsidies; stumpage prices for trees cut down on federal land were long criticized as too low. Then they were quiet on the subject. But now that most American-produced lumber comes from private forests, government subsidies are anathema.
In Seattle, Robb Dunn, president of a chain of ten lumber stores, says his customers will just have to put up with higher prices. Some reckon the tariff will increase new-home prices by as much as $1500. That may be a bit high; although lumber prices have gone up lately, they are still below the peak reached last summer. And rising interest rates may slow the American housing market, cutting demand.
The two sides hope to continue talks. One way out might be an agreement under which Canada taxes its lumber companies until it reforms its pricing policies to America’s satisfaction. But Mr. Allan, for one, is not optimistic. The US, he says, has not negotiated in good faith “Its government just can’t get a grip in its timber industry, which is too powerful.”
1. why do Americans not feel happy about Canadian softwood
A 30% of Canadian softwood came into America.
B it produces hard feelings between the two countries.
C Canada is dumping it into America.
D it is sold at a subsidized price.
2. we can infer from the text that
A Canadian central government sets the price for its forest
B the uncut trees were giver to companies for tree
C Canadian companies pay 60% less for softwood export
D the experts were hired to evaluate the behavior of lumber industry
3. what is Canadians’ answer to Americans’ accusation
A stumpage fees at present are high rather than low.
B no protection is received from Canadian government.
C raising stumpage fees will not solve the problem.
D lumber price includes many expensive components.
4. why are the Americans silent on their own lumber subsidy
A they no longer exist
B Americans apply a double standard.
C little lumber comes from federal land.
D private forests monopolise the market.
5. what will probably happen because of this trade war
A demand for wooden house will fall.
B customers will have to pay high prices.
C Canada will place higher tax on lumber industry.
D the US will negotiate the matter with good faith.
Text 3
Violent criminals with something to hide have more reason than ever to be paranoid about a tap on the shoulder which could send them to jail. Queensland police are working through a backlog of unsolved murders with some dramatic success. Greater cooperation between the public and various law enforcement agencies is playing a role, but new genetic-testing techniques are the real key to providing the vital evidence to mount a prosecution.
Evidence left behind at the scene of any murder is guaranteed to outlive the person who left is. A blood, saliva or tissue sample the size of a pin, kept dry and out of sunlight, will last several thousand years. From it, scientific analysis now can tell accurately the sex of the person who left it.
When matched against a sample from a crime suspect, it can indicate with million-to-one certainty whether the samples come from the same source. Only twins share identical DNA. So precise is the technology if the biological parents of a suspect agree to provide a sample, forensic scientists can work out the rest for themselves without cooperation from the suspect.
Queensland forensic scientists have been using the DNA testing technology since 1992, and last year they were recognized internationally for their competence in positive individual identification. That is part of the reason 20 of Queensland’s most puzzling unsolved murders dating to 1952 are being actively investigated. There also have been several recent arrests for unsolved murders.
Forensic evidence was instrumental in chares being laid over the bashing death of waitress Tasha Douty on Bromptong Island in 1983. Douty’s blood-splattered, naked body was found on a nude sunbathing beach at Dinghy Bay on the island. Footprints in the sand indicated that the killer had grappled with the 41-year-old mother who had fled up the beach before being caught and beaten to death.
According to Leo Freney, the supervising forensic scientist at the John Centre at Brisbane’s Griffith University, DNA testing has become an invaluable tool for police. Its use is in identifying and rejecting suspects. In fact, he says, it eliminates more people than it convicts.
“It is easily as good as fingerprints for the purpose of identification,” he says. “In the case of violent crime it is better than fingerprints. You can’t innocently explain things like blood and semen at a crime scene where you may be able to innocently explain fingerprints.” In Queensland, a person who has been arrested on suspicion of an offence can be taken before a magistrate and ordered to provide a sample of body fluid by force if necessary.
1. Evidence left behind at the scene of a crime is all of the following EXCEPT
A blood
B tissue
C fingerprint
D pin
2. the Queensland police has made dramatic progress in investigating unresolved murders because of .
A greater cooperation between suspects and the police
B possibilities offered by the DNA testing technology
C police competence in positive individual identification
D new evidence left at the scene of these murders
3. before her murder, Tasha Douty was on Brompton Island probably
A working as a waitress
B spending her holiday
C having a bath in the sun
D swimming on the beach
4. according to Leo Freney, DNA testing is a valuable tool because it
