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！

老师例5，7的平方49，没有超过100啊，为什么不能选？

老师，这道题你换了好几次思路，真的没听懂！谢谢！

老师这道题没懂，我也不会拆分！

老师这个是怎么解出来的？拆分？这么大的数不会拆哦

老师，这里不懂条件1怎么算出来的， 40怎么来的？谢谢！

PS：|nx-8|≤4，有多少个整数n使得恰好只有2个整数解x？ 求问may老师

老师，这里看不懂二分之Q减一是什么？

老师例7的A怎么能成立呢？把2带进去，一个方程俩未知数啊？

讨论的71那三个情况不是3的倍数？70那俩是三的倍数？213能被三整除啊，其他不能整除怎么70那些都是3的倍数呢？谢谢哦！

我觉得这道题应该选E，因为当ab同时大于1，原命题成立，当ab同时大于0小于1，原命题不成立