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Scattered through the seas of the world are billions of tons of small plants and animals called plankton. Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals. Plankton has been described as the equivalent of the grasses that grow on the dry land continents, and the comparison is an appropriate one. In potential food value however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates each year. The sea’s plankton generates more than twice as much.

Despite its enormous food potential, little effort was made until recently to farm plankton as we farm grasses on land. Now marine scientists have at last begun to study this possibility, especially as the sea’s resources loom even more important as a means of feeding an expanding world population.

No one yet has seriously suggested that “planktonburgers” may soon become popular around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists.

One type of plankton that seems to have great harvest possibilities is a tiny shrimplike creature called krill. Growing to two or three inches long, krill provide the major food for the giant blue whale, the largest animal ever to inhabit the Earth. Realizing that this whale may grow 100 feet and weigh 150 tons at maturity, it is not surprising that each one devours more than one ton of krill daily.

Krill swim about just below the surface in huge schools sometimes miles wide, mainly in the cold Antarctic. Because of their pink color, they often appear as a solid reddish mass when viewed from a ship or from the air. Krill are very high in food value. A pound of these crustaceans contains about 460 calories—about the same as shrimp or lobster, to which they are related.

If the krill can feed such huge creatures as whales, many scientists reason, they must certainly be contenders as new food source for humans.

1.Which of the following best portrays the organization of the passage?

A.The author presents the advantages and disadvantages of plankton as a food source.

B.The author quotes public opinion to support the argument for farming plankton.

C.The author classifies the different food sources according to amount of carbohydrate.

D.The author makes a general statement about plankton as a food source and then moves to a specific example.

2.According to the passage, why is plankton regarded to be more valuable than land grasses?

A.It is easier to cultivate.

B.It produces more carbohydrates.

C.It does not require soil.

D.It is more palatable.

3.Why does the author mention “planktonburgers”?

A.To describe the appearance of one type of plankton.

B.To illustrate how much plankton a whale consumes.

C.To suggest plankton as a possible food sources.

D.To compare the food values of beef and plankton.

4.What is mentioned as one conspicuous feature of krill?

A.They are the smallest marine animals.

B.They are pink in color.

C.They are similar in size to lobsters.

D.They have grass like bodies.

5.The author mentions all of the following as reasons why plankton could be considered a human food source except that it is ___.

A.high in food value.

B.in abundant supply in the oceans.

C.an appropriate food for other animals.

D.free of chemicals and pollutants.

时间:2020-06-16

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Which is safer-staying at home, traveling to work on public transport, or working in the office? Surprisingly, each of these carries the same risk, which is very low. However, what about flying compared to working in the chemical industry? Unfortunately, the former is 65 times riskier than the latter! In fact, the accident rate of workers in the chemical industry is less than that of almost any of human activity, and almost as safe as staying at home.

The trouble with the chemical industry is that when things go wrong they often cause death to those living nearby. It is this which makes chemical accidents so newsworthy. Fortunately, they are extremely rare. The most famous ones happened at Texas City (1947),Flixborough (1974), Seveso (1976), Pemex (1984) and Bhopal (1984)。

Some of these are always in the minds of the people even though the loss of life was small. No one died at Seveso, and only 28 workers at Flixborough. The worst accident of all was Bhopal, where up to 3,000 were killed. The Texas City explosion of fertilizer killed 552. The Pemex fire at a storage plant for natural gas in the suburbs of Mexico City took 542 lives, just a month before the unfortunate event at Bhopal.

Some experts have discussed these accidents and used each accident to illustrate a particular danger. Thus the Texas City explosion was caused by tons of ammonium nitrate(硝酸铵),which is safe unless stored in great quantity. The Flixborough fireball was the fault of management, which took risks to keep production going during essential repairs. The Seveso accident shows what happens if the local authorities lack knowledge of the danger on their doorstep. When the poisonous gas drifted over the town, local leaders were incapable of taking effective action. The Pemex fire was made worse by an overloaded site in an overcrowded suburb. The fire set off a chain reaction os exploding storage tanks. Yet, by a miracle, the two largest tanks did not explode. Had these caught fire, then 3,000 strong rescue team and fire fighters would all have died.

1.Chemical accidents are usually important enough to be reported as news because ____.

A.they are very rare

B.they often cause loss of life

C.they always occur in big cities

D.they arouse the interest of all the readers

2.Which of the following statements is true?

A.Working at the office is safer than staying at home.

B.Traverlling to work on public transport is safer than working at the office.

C.Staying at home is safer than working in the chemical industry.

D.Working in the chemical industry is safer than traveling by air.

3.According to passage, the chemical accident that caused by the fault of management happened at ____.

A.Texas city B.Flixborough C.Seveso D.Mexico City

4.From the discussion among some experts we may coclude that ____.

A.to avoid any accidents we should not repair the facilities in chemical industry

B.the local authorities should not be concerned with the production of the chemical industry

C.all these accidents could have been avoided or controlled if effective measure had been taken

D.natural gas stored in very large tanks is always safe

5.From the passage we know that ammonium nitrate is a kind of ____.

A.natural gas, which can easily catch fire

B.fertilizer, which can't be stored in a great quantity

C.poisonous substance, which can't be used in overcrowded areas

D.fuel, which is stored in large tanks

时间:2020-06-16

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More attention was paid to the quality of production in France at the time of Rene Coty. Charles Deschanel was then the financial minister. He stressed that workmanship and quality were more important than quantity for industrial production. It would be necessary to produce quality goods for the international markets to compete with those produced in other countries. The French economy needed a larger share of international market to balance its import and export trade.

French industrial and agricultural production was still inadequate to meet the immediate needs of the people, let alone long-ranged developments. Essential imports had stretched the national credit to the breaking point. Rents were tightly controlled, but the extreme inflation affected general population most severely through the cost of food. Food costs took as much as 80 percent of the worker's income. Wages, it is true, had risen. Extensive family allowances and benefits were paid by the state, and there was fulltime and overtime employment. Taken together, these factors enabled the working class to exist but allowed them no sense of security. In this discouraging situation, workmen were willing to work overseas for higher wages.

The government was unwilling to let workers leave the country. It was feared that migration of workers would reduce the labor force. The lack of qualified workers might hinder the improvement in the quality of industrial products produced. Qualified workers employed abroad would only increase the quantity of quality goods produced in foreign countries. Also the quantity of quality goods produced in France would not be able to increase as part of its ualified labor force moved to other countries.

1. The purpose of the passage is to_______.

A. explain the French government's emphasis on quality products

B. discuss Charles Deschanel's contribution to the French industrial development

C. compare the quality of French goods with that of foreign goods

D. show French workmen's enthusiasm to seek well-paid jobs in foreign countries

2. It can be inferred from the passage that at the time of Rene Coty .

A. France was still at the first stage of industrial development

B. French workers were better paid than the workers in any other European countries

C. the unemployment rate in France was comparatively higher than that in other European countries

D. French workers were able to live better with the increase in their wages

3. It is implied in the passage that at that time_______.

A. France had a very large share of international market

B. the import and export trade in France was making a successful advance

C. demand and supply in France was barely balanced

D. France was experiencing economic depression

4. Which of the following is the best indicator of the extreme inflation in France?

A. Eighty percent increase in the prices of consumer goods. B. High cost of food.

C. High rents for houses. D. Lack of agricultural products.

5. Which of the following is NOT mentioned in the passage?

A. Rents in France were tightly controlled.

B. France was flooding the international market with inferior product s.

C. French workers were prohibited from going abroad to find jobs.

D. The migration of French workers would hinder the improvement of quality in industrial production.

时间:2020-06-16

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The matter is not to be ____.

时间:2020-06-16

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