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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 shrimp like 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. The author mentions all of the following as reasons why plankton could be considered a human food source except that it is ().
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In the last 12 years total employment in the United States grew faster than at any time in the peacetime history of any country—from 82 to 110 million between 1973 and 1985— that is, by a full one third. The entire growth, however, was in manufacturing and especially in no-blue-collar jobs...This trend is the same in all developed countries, and is, indeed, even more pronounced in Japan. It is therefore highly probable that in 25 years developed countries such as the United States and Japan will employ no larger a proportion of the labor force In manufacturing than developed countries now employ in farming—at most, 10 percent. Today the United States employs around 18 million people in blue-collar jobs in manufacturing industries. By 2010, the number is likely to be no more than 12 million. In some major industries the drop will be even sharper. It is quite unrealistic, for instance, to expect that the American automobile industry will employ more than one-third of its present blue-collar force 25 years hence, even though production might be 50 percent higher.If a company, an industry or a country does not in the next quarter century sharply increase manufacturing production and at the same time sharply reduce the blue-collar work force, it cannot hope to remain competitive—or even to remain "developed." The attempt to preserve such blue-collar jobs is actually a prescription for unemployment...This is not a conclusion that American politicians, labor leaders or indeed the general public can easily understand or accept. What confuses the issue even more is that the United States is experiencing several separate and different shifts in the manufacturing economy. One is the acceleration of the substitution of knowledge and capital for manual labor. Where we spoke of mechanization a few decades ago, we now speak of "robotization" or "automation". This is actually more a change in terminology than a change in reality. When Henry Ford introduced the assembly line in 1909, he cut the number of man-hours required to produce a motor car by some 80 percent in two or three years—far more than anyone expects to result from even the most complete robotization. But there is no doubt that we are facing a new, sharp acceleration in the replacement of manual workers by machines—that is, by the products of knowledge. This passage may have been excepted from ().
A great deal of attention is being paid today to the so-called digital divide—the division of the world into the info (information) rich and the info poor. And that (31) does exist today. My wife and I lectured about this looming danger twenty years ago. What was less (32) then, however, were the new, positive (33) that work against the digital divide. (34) , there are reasons to be (35) .There are technological reasons to hope the digital divide will narrow. As the Internet becomes more and more (36) , it is in the interest of business to universalize access-after all, the more people online, the more potential (37) there are. More and more (38) , afraid their countries will be left (39) , want to spread Internet access. Within the next decade or two, one to two billion people on the planet will be (40) together. As a result, I now believe the digital divide will (41) rather than widen in the years ahead. And that is very good news because the Internet may well be the most powerful tool for (42) world poverty that we’ve ever had.Of course, the use of the Internet isn’t the only way to (43) poverty. And the Internet is not the only tool we have. But it has (44) potential.To (45) advantage of this tool, some poor countries will have to get over their outdated anti-colonial prejudices (46) respect to foreign investment. Countries that still think foreign investment is a/an (47) of their sovereignty might well study the history of (48) (the basic structural foundations of a society) in the United States. When the United States built its industrial infrastructure, it didn’t have the capital to do so. And that is (49) America’s Second Wave infrastructure— (50) roads, harbors, highways, ports and so on-were built with foreign investment. 46().
A great deal of attention is being paid today to the so-called digital divide—the division of the world into the info (information) rich and the info poor. And that (31) does exist today. My wife and I lectured about this looming danger twenty years ago. What was less (32) then, however, were the new, positive (33) that work against the digital divide. (34) , there are reasons to be (35) .There are technological reasons to hope the digital divide will narrow. As the Internet becomes more and more (36) , it is in the interest of business to universalize access-after all, the more people online, the more potential (37) there are. More and more (38) , afraid their countries will be left (39) , want to spread Internet access. Within the next decade or two, one to two billion people on the planet will be (40) together. As a result, I now believe the digital divide will (41) rather than widen in the years ahead. And that is very good news because the Internet may well be the most powerful tool for (42) world poverty that we’ve ever had.Of course, the use of the Internet isn’t the only way to (43) poverty. And the Internet is not the only tool we have. But it has (44) potential.To (45) advantage of this tool, some poor countries will have to get over their outdated anti-colonial prejudices (46) respect to foreign investment. Countries that still think foreign investment is a/an (47) of their sovereignty might well study the history of (48) (the basic structural foundations of a society) in the United States. When the United States built its industrial infrastructure, it didn’t have the capital to do so. And that is (49) America’s Second Wave infrastructure— (50) roads, harbors, highways, ports and so on-were built with foreign investment. 42().
Write a note of about 50-60 words based on the following situation: You have just received a phone call from your mother at the hospital. She is ill and you must get there right away. Write a note to your teacher to ask for leave. Marks will be awarded for content, organization, grammar and appropriateness.
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