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！

有三组滑冰运动员，第一组全是single women，6个人，第二组是paired，3组，第三组是single men，5个人，他们的出场顺序是single women-paired-single men，问一共有多少种order？ （1）6+3+5 （2）6！*3！*5！ （3）6*3*5 （4）（6+3+5）！

一个数能被10^r 整除，不能被10^（r+1）整除，求r？ （1）这个数能被2^5整除，不能被2^6整除 （2）这个数能被5^6整除，不能被5^7整除

30个蓝球10个红球，摸一个放回去再摸一个，摸到两个颜色一样的就结束。第一个摸的是红球，问在摸到两个蓝球前摸到红球的概率是多少。

两个整数XY，问是否知道XY的值？ （1）X,Y的common divisor是（一个值） （2）X/Y=（一个值）

一个rectangular block，求表面积？ （1）each two面的面积是11，其中一边长（某个数） （2）一个边的边长是（某个数）

PS：俩骰子每面各是1-6，且每投一次各个数字冲上的概率一致。问同时扔这俩，俩加和是9或者5的概率？选了2/9。 老师您好，解析给是：共有6*6=36种，等于9的情况3+6,4+5,5+4,6+3。等于5的情况1+4,2+3,3+2,4+1。一共8个，所以是8/36=2/9。这是考虑了顺序的，8种情况是考虑到顺序，但我觉得不应该考虑顺序，应该只有4种。请指点。

一道数学机经题，没有具体数字麻烦老师讲下思路~~谢谢~~ DS： 有10个马拉松运动员平均成绩是2分32秒，问能否推出range？ 条件1：最快5个的range是XX 条件2：最慢5个的range是XX 构筑：不确定，选了e 构筑答案：E 整理菌答案：详见解析 解析: 整理菌列了几组数字来计算，感觉不能推出E。 但应该可以根据平均成绩以及人数，进行系统的计算。欢迎讨论！！

还是数学机经题~想问一下老师这个题不用反证法可以解吗？？或者反证法合理吗？？谢谢~~ DS：问h是不是prime number 条件1：h的factor都大于根号h 条件2：h的factor都大于h/2 反证法： 假设h = a*b 且a, b >1， h不是质数。 条件1： a，b>根号h，then H > 根号h*根号h = h， 推出矛盾，所以h不能写成两个大于1的数相乘，所以h是质数； 条件2： 同理 H>2/h*2/h=h^2/4 推出h<4, then h = 2 or 3, 是质数， 与假设矛盾。所以h是质数。 选D

有一个矩形的green sport field，长为L，宽为W，周围是一圈walking trace，宽为d，其中四个角是矩形的，面积分别为半径为d的圆形的4分之1，求walking trace的面积 条件1：矩形周长是36 条件2：d=20

平行四边形边长为6，面积为18，求角度可能是以下哪个？ 30 45 60 90 120