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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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下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。 第一篇 One of the greatest mysteries of the world, for ’which scientist have so far been unable to find any satisfactory explanation, is the Bermuda Triangle, sometime called "the Graveyard of the Atlantic." This is an area of the western Atlantic between Bermuda and Florida, roughly triangular in shape where since 1945 at least a hundred ships and planes and over a thousand people have disappeared. No wreckage had been found, no bodies, lifebelts or any other evidence of disater. It is as if these planes, ships and people had never existed. In some cases a routine radio message has been received from aircraft reporting everything in order a few minutes before all contact was lost, in others a weak S. O. S message has been picked up and, in perfect weather, inexplicable references to fog and loss of bearings. In the extraordinary case of five U. $. navy planes disappearing on a routine mission from Florida, the rescue place sent to locate them vanished also. There have been references to the curious white light or haze which is a feature of the sea in part of this area, and it is interesting to note that not only was this light, or streaks of light, observed by the astronauts on their way to space, but was also noted by Columbus, five centuries ago. Whether this light has any connection with the mysterious disappearance is unknown-it is just another curious circumstance as yet unexplained. Many theories, some bordering on the fantastic, have been advanced to account for the disturbing incidents that occur in the area of the Bermuda Triangle. It has been asked whether these disappearances are caused by extraterrestrial activity, by some undiscovered source of energy, or some dimension of time or space unguessed at by Man. This is no answer and speculation continues as anxiety increases. What is the most puzzling feature of the incidents that have occurred in the Bermuda Triangle area
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