题目内容
Directions: There are 5 reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C, and D. You should decide on the best choice and mark your answer on the ANSWER SHEET by blackening the corresponding letter in the brackets. A man-made chemical that attracts male gypsy moths by duplicating the natural attractant of female gypsy moths has been patented as No. 3,018,219. Dr. Martin Jacobson of Silver Spring, Md., assigned patent rights to the U. S. Government as represented by the Secretary of Agriculture. The chemical can be used to detect gypsy moth infestations, as well as to control the insects. The gypsy moth does serious damage to forest and shade trees in New England and eastern New York State. The caterpillars, or larvae, of gypsy moths eat the leaves of trees, often causing death by a single attack. Losses of hardwood trees have been estimated at tens of millions of dollars from a 20-year study. Gypsy moths were prevented from spreading to other U. S. forest areas by using the natural attractant of the female to detect infestations, then spraying with chemicals such as DDT to kill the insects. Since the lure could previously be obtained only by clipping the last two abdominal segments of the virgin female moth, extracting the segments with benzene and then processing to stabilize the chemical, the procedure was expensive. Another difficulty was that, as the gypsy moth population declined, it became increasingly hard to obtain the females needed for lure production. Dr. Jacobson overcame both these difficulties by discovering a synthetic method for making the female’s attractant chemical. The chemical is known as 12-acetoxy-l-hydroxycis-9- octadecene. It is so potent that the fraction of a drop produced by the female is 200,000 times more than the amount needed to catch a mate. The synthetic chemical is also very powerful--it works in amounts about equivalent to one drop in a box car. The flightless female gypsy moth mates only once a year and, as soon as she does, an enzyme switches off production of the sex attractant. The winged male, however, call mate several times and it is because of this that the chemical is being used for pest control. By using a mixture of attractant and DDT in traps lined with a sticky substance, enough males can be caught to reduce the gypsy moth population substantially. We may assume that Dr. Jacobson assigned patent rights to the United States Government because he ______.
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理财规划是一个一生的财务计划，同时理财规划又是动态的，不断调整的，不是一成不变的。( )
A little more than a century ago, Michael Faraday, a noted British physicist, managed to gain audience with a group of high government officials, to demonstrate an electrochemical principle, in the hope of gaining support for his work. After observing the demonstration closely, one of the officials remarked bluntly, "It’s a fascinating demonstration, young man, but just what practical application will come of this" "I don’t know," replied Faraday, "but I do know that 100 years from now you’ll be taxing them." From the demonstration of a principle to the marketing of products derived from that principle is often a long, involved series of steps. The speed and effectiveness with which these steps are taken are closely related to the history of management, the art of getting things done. Just as management applies to the wonders that have evolved from Faraday and other inventors, so it applied some 4,000 years ago to the workings of the great Egyptian and Mesopotamian import and export firms...to Hannibal’s remarkable feat of crossing the Alps in 218 B.C. with 90,000 foot soldiers, 12,000 horsemen and a "conveyor belt" of 40 elephants...or to the early Christian Church, with its world-shaking concepts of individual freedom and equality. These ancient innovators were deeply involved in the problems of authority, division of labor, discipline, unity of command, clarity of direction and the other basic factors that are so meaningful to management today. But the real impetus to management as an emerging profession was the Industrial Revolution. Originating in 18th-century England, it was triggered by a series of classic inventions and new processes, among them John Kay’s Flying Shuttle in 1733, James Hargreaves’ Spinning Jenny in 1770, Samuel Crompton’s Mule Spinner in 1779 and Edmund Cartwright’s Power Loom in 1785. Management is defined as ______.
函数Mal("123.45")+Val("233.6")的值是 【7】 。
The coastlines on the two sides of the Atlantic Ocean present a notable parallelism: the easternmost region of Brazil, in Pernambuco, has a convexity that corresponds almost perfectly with the concavity of the African Gulf of Guinea, while the contours of the African coastline between Rio de Oro and Liberia would, by the same approximation, match those of the Caribbean Sea. Similar correspondences are also observed in many other regions of the earth. This observation began to awaken scientific interest about sixty years ago, when Alfred Wegener, a professor at the University of Hamburg, used it as a basis for formulating a revolutionary theory in geological science. According to Wegener, there was originally only one continent or landmass, which he called Pangea. Inasmuch as continental masses are lighter than tile base on which they rest, he reasoned, they must float on the substratum of igneous rock, known as sima, as ice floes float on the sea. Then why, he asked, might continents not be subject to drifting The rotation of the globe and other forces, he thought, had caused the cracking and, finally, the breaking apart of the original Pangea, along an extensive line represented today by the longitudinal submerged mountain range in the center of the Atlantic. While Africa seems to have remained static, the Americas apparently drifted toward the west until they reached their present position after more than 100 million years. Although the phenomenon seems fantastic, accustomed as we are to the concept of the rigidity and immobility of the continents, on the basis of the distance that separates them it is possible to calculate that the continental drift would have been no greater than two inches per year. The title below that best expresses the main idea of this passage is ______.
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