Years before the advent of plate tectonics―the widely accepted theory, developed in the mid-1960's, the holds that the major features of Earth's surface are created by the horizontal motions of Earth's outer shell, or lithosphere―a similar theory was rejected by the geological community. In 1912, Alfred Wegener proposed, in a widely debated theory that came to be called continental drift, that Earth's continents were mobile. To most geologists today, Wegener's The origin of Continents and Oceans appears an impressive and prescient document, containing several of the essential presumptions underlying plate tectonics theory: the horizontal mobility of pieces of Earth's crust; the essential difference between oceanic and continental crust; and a causal connection between horizontal displacements and the formation of mountain chains. Yet despite the considerable overlap between Wegener's concepts and the later widely embraced plate tectonics theory, and despite the fact that continental drift theory presented a possible solution to the problem of the origin of mountains at a time when existing explanations were seriously in doubt, in its day Wegener's theory was rejected by the vast majority of geologists. Most geologists and many historians today believe that Wegener's theory was rejected because of its lack of an adequate mechanical basis. Stephen Jay Gould, for example, argues that continental drift theory was rejected because it did not explain how continents could move through an apparently solid oceanic floor. However, as Anthony Hallam has pointed out, many scientific phenomena, such as the ice ages, have been accepted before they could be fully explained. The most likely cause for the rejection of continental drift―a cause that has been largely ignored because we consider Wegener's theory to have been validated by the theory of plate tectonics―is the nature of the evidence that was put forward to support it. Most of Wegener's evidence consisted of homologies―similarities of patterns and forms based on direct observations of rocks in the field, supported by the use of hammers, hand lenses, and field notebooks. In contrast, the data supporting plate tectonics were impressively geophysical―instrumental determinations of the physical properties of Earth garnered through the use of seismographs, magnetometers, and computers. 我选了E considerable overlap前面是despite XXX说明这个是个成就，他和后面的反对W的观点的事情是相反的。所以感觉D说用这个词的目的是解释为啥W理论。请老师辨析DE！谢谢！

DS：如果x和y是≥0的数，问3^xy次方是多少？ 条件1：5^x=11^y 条件2：3^x=9^y 请问这题答案是B吗？谢谢老师！

不明白这道题的总体积为什么是（x+2）(y+2)(z+2)而不是（x+1）(y+1)(z+1);厚度不是1吗？谢谢！

我觉得这题答案应该是A吧？∵105拆分质因数可得105=3*5*7（3个完全不同的质因数）∴x+y+z=15。怎么会是C呢？？？？

向May提问，我觉得这题情况会分得很复杂，想听下老师的思路？

想向May老师提问。这题我知道条件1单独成立，但对条件2没什么思路，只能想到穷举法，当p等于2*5,3*5,3*5,2*3,2*5,3*5时，m等于2*3,2*3,2*5,5,3,2，然后一个个除发现有的余数是1，有的余数大于1，条件2单独不成立。想问老师这个思路对吗？有没有更加简洁的思路？

不懂此题。已知有A,B,C和D共4个人；问：现在从这四个人中选出3人，是ACD的概率是多少？请详细解释，谢谢老师！

不理解第一个条件均值如何得出关于6倍数的结论，是连续7个数除7余数为5则为6的倍数，所以有一个6的倍数？

不理解第一个条件均值如何得出关于6倍数的结论，是连续7个数除7余数为5则为6的倍数，所以有一个6的倍数？

第8题的思路是以BC为底，从F向BC做垂线，跟BC交点H，FH为三角形FBC的高。然后三角形BFH跟三角形BDC相似，h：30=BF：BD，但是BF长度未知，望老师解答。

第8题的思路是以BC为底，从F向BC做垂线，跟BC交点H，FH为三角形FBC的高。然后三角形BFH跟三角形BDC相似，h：30=BF：BD，但是BF长度未知，望老师解答。