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阅读下面这篇短文，短文后列出7个句子，请根据短文的内容对每个句子做出判断。如果该句提供的是正确信息，请选择A；如果该句提供的是错误信息，请选择B；如果该句的信息文章中没有提及，请选择C。 Even plants can run a fever, especially when they’ re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away—straight up. A decade ago, adapting the infrared(红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide(杀虫剂) spraying rather than rain poison on a whole field, which invariably includes plants that don’t have pest(害虫) problems. Even better, Paley’s Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an infrared scanner measured the heat emitted by crops. The data Were transformed into a color-coded map showing where plants were running "fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would. The bad news is that Paley’ s company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States," says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago. Plants will emit an increased amount of heat when they are in poor physical condition.
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在窗体上画一个名称为Command1的命令按钮，然后编写如下程序：Private Sub Command1_ Click() Static x As Integer Static y As Integer Cls y=1 y=y+5 x=y +x Print x, yEnd Sub程序运行时，三次单击命令按钮Command1后，窗体上显示的结果为______。
阅读下面这篇短文，短文后列出7个句子，请根据短文的内容对每个句子做出判断。如果该句提供的是正确信息，请选择A；如果该句提供的是错误信息，请选择B；如果该句的信息文章中没有提及，请选择C。 Even plants can run a fever, especially when they’ re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away—straight up. A decade ago, adapting the infrared(红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide(杀虫剂) spraying rather than rain poison on a whole field, which invariably includes plants that don’t have pest(害虫) problems. Even better, Paley’s Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an infrared scanner measured the heat emitted by crops. The data Were transformed into a color-coded map showing where plants were running "fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would. The bad news is that Paley’ s company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States," says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago. Farmers can save a considerable amount of pesticide by consulting infrared scanning experts.
阅读下面的短文，文中有15处空白，每处空白给出4个选项，请根据短文的内容从4个选项中选择1个最佳答案。 One of the most important technological developments during the 1980s has been the emergence of optical fiber communication as a major international industry. One indication of the (51) of this development is the total (52) of installed fiber, which was estimated to be 3.2 million kilometers in the U.S. alone by the end of 1987. Over 90% of this fiber was placed. (53) during the time period of 1982—1987. Long-haul trunk installations(长途干线设施) have dominated, (54) for about 95% of the fiber in the U.S. In the early 1950s the researchers who produced the first clad glass optical fibers were not (55) of using them. for communications. (56) , fiber optics was already a well-established commercial technology when the famous paper by Kao and Hockham, (57) the use of low-loss optical fibers for communication, appeared in 1966. The first low-loss silica fiber was described in a publication which appeared in October of 1970. The date of this publication is sometimes (58) as the beginning of the era of fiber communication. Although this development did receive (59) attention in the research community at- the time, it was far from inevitable that a major industry would evolve. The technological barriers appeared (60) because there were serious doubts as to (61) these fiber components could ever be produced economically enough, but the market potential was very significant. (62) , research and development activity expanded rapidly, and a number of important issues were (63) during the early 1970s. During the middle and late 1970s, the rate of progress towards marketable products accelerated as the emphasis (64) from research to engineering. Fibers with losses approaching the Payleigh limit of 2 dB/km at a wavelength of 0.8um were produced. By 1980 improvement in component performance, cost, and reliability led to major commitments (65) the part of telephone companies.
阅读下面短文，回答问题。 树是一部活档案，树干的年轮就是历史的记录。1901年，美国人道格拉斯发现居住地附近新近砍伐留下的树桩上，都有相同的图案纹理，譬如说，这些树木年轮的外面三圈都较宽，这表明近3年居住地附近环境与气候条件较好，树木生长较快。相反的结论也可以由此得出。这个发现促使道格拉斯致力于树木年轮的深入研究。他用“同一地区，同时期年轮模式相同”的假设，以“接龙”的方式，来推算老树的初生年份。比如，有一棵被砍伐的百年古树，其砍伐年代不详，但是它的年轮中有一圈与当地一棵1864年砍下的大树的年轮最外圈相吻合。由于最外圈是被砍伐当年的年轮，因此这相吻合的一圈为1864年的年轮。由此向内按每进一圈是一年的方法推算，就可以算出这棵树大约哪一年栽种的。 一些科学家还根据年轮推算出发生过酸雨的年份。哥伦比亚大学的雅格比解释说，随着树木越长越老，年轮也变得越来越窄，而酸雨对树木恰恰起着相反在作用。年轮还可以记录下火山爆发与地震。火山爆发时，大量灰尘与气体进入同温层，遮住了阳光，这会使温度降到冰点以下，给树木留下一道叫做“霜轮”的特殊标记。东印度群岛坦波拉山爆发曾使1816年成了“没有夏天的一年”，这个标记甚至出现在南非的树木上。地震也可以给树木造成损害，使树在以后的一些年中形成较窄的年轮。由此看来，倘若说树木年轮“泄漏天机”，似乎并不为过。 (佚名《年轮》) 年轮的“圈迹”较宽，证实以下“较好”的一项是：
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