0821一战分手(V41 Q49 730）放狗感恩CD 真的感恩CD

Ariel_zzzzy

阅读前两篇印象不深了着重讲一下后两篇
第三篇讲的是copper 长 一屏多
第一段 copper的开采什么的 主要要知道p-copper（p打头的单词+copper，应该是copper的一种）比较稀少，科学家认为p-copper的产生和火山有关，但是几乎没有有效的实例可以证明
第二第三段都在说 虽然没有有效实例 但还是有一些间接（好像用的是indirect之类的词）可以证明 第二第三段各一个例子
第二段例子讲的是（大概是p-copper附近的）一个石头还是什么的（印象里c打头，不是很确定）的形状是vertical的，这种vertical的形状与earth surface破裂/冲破有关，而earth surface 冲破与火山有关
第三段例子讲的是p-copper密集区是在太平洋吧好像 反正一个地震带，地震带上火山很多
考了主旨题，很好选
考了两个细节题 两个例子各一个
第二段考的是 vertical的形状说明了什么，我选的是带earth surface 破裂的一项
第三段考的记不清了55555
第四篇讲的好像是人脑感知和反应系统一类的 很短 一屏不到
第一段讲了什么 有些模糊 好像是人们感觉到（或者是看到）的东西-----形状，动态。。。都会由各种路径传递到大脑（原文用的是另一个单词，不是大脑，但理解成大脑没问题），对于人们看到的不同东西大脑处理的速度是不一样的
第二段就更具体一点，讲的是人脑处理信息总是要等最晚到达大脑的信息到了以后才会出结果，这个时间差大约是十分之一秒。后面有两句话，我的理解是虽然差了这十分之一秒，但这点误差还是acceptable的（很绕，一直没理解到底这点时间差是不是acceptable，但我这里考到了两个题）

数学
啊数学考着考着觉得自己可能有点掉库 心态就崩了 后面IR也在乱做 还好被verbal拉住了
1.PS 5 12 23 45 89 90（数字随便列的，不影响）are randomly ordered，问正好顺序或逆序的可能性
2. DS 有一个test，已经做了64次（好像），中位数是78；又多做了3次，变成67次（次数不确定，但肯定是做3次之前偶数），问中位数还是不是78
    条件1：给了后三次的range是12
    条件2：给了后三次中位数是80
3. DS fx=ax^2+bx+c 问fx是否等于0
    条件1：f（4）=0
    条件2：f(-b/a)=0
4. DS (n+3)!-(n+2)!=(7)(7!)
    条件1 条件2 都是n的一元二次方程 都能解出n=5
5. DS　p绝对值小于100 属于Small区域 p绝对值大于1000 属于large区域 其他属于medium区域　问能否确定ｐ的区域
　条件一　忘了好像可以
　条件二　p/10属于medium区域
6. ＰＳa^2-a>0,a^3-a<0 求a属于的范围
　选onlyａ<-1好像

逻辑和语法 实在是大脑空空如也 但印象里语法有点难 大多是考逻辑语义 靠了很多时态（我很不擅长时态） 几乎没有但凭语法点可以做出的题
逻辑还好，考了无数道assumption，甚至我有一道assumption斗胆选了没有否定词的那一项，考到了boldface，但题目很短很简单

考前三天换库，一刷能过真的很感激CD了，所以就算记得不是很清楚还是尽力回忆了一点
最后再想分享一点自己复习经历
我整个备考经历一个月多吧 期间又一直在实习 其实复习效率不高
前半个月浑浑噩噩刷og和prep，一开始还有提高，半个月过去就进了瓶颈期
然后我就开始看错题 句子改错整理了一堆可能出现的错误 对着题目在错误旁边画正字（平行，比较对象对等，more-than- ，主谓一致，句子碎片，which不能指代前面的句子，doing做修饰时主语能否发出该动作 这几个完胜）就是培养自己对句子中错误的一种敏感吧 但是现在那么注重逻辑语义也不知道这样还有没有用
逻辑就根据题目整理逻辑链，慢慢的会觉得其实很多逻辑链是相似的，是有共同内核的。还有逻辑我觉得很要紧的点就是明确conclusion或者目的，不要有任何的往外衍生。
阅读emmmmm我是死脑筋所有文章都喜欢从头看到尾，考高考考雅思考四六级，但我读文章的确比较快，而且我在kkk上试过如果读顺了文章，做一道题的时间大致是30s，所以pace是ok的
数学，考了49就不讲了
ir和写作我几乎就是放弃状态（实习太累了。。。。。。
就这样和gmat分手啦~祝大家都能早日考出理想的成绩鸭
最后再说一句 我爱CD!!!!!!!!

divedeep

恭喜楼主呀

BOYisme

数学：
1. 2/A66
2. E
3. B
4. 如果能解出 n=5，那么选...D?    主要是一元二次有2个解，所以也有可能是C
5. 条件二充分，条件一LZ说充分的话，就D？
6. a<-1

BOYisme

另外恭喜楼主！

wukelun

感谢 恭喜楼主

Yanling_

恭喜楼主，吸吸欧气！

billyisfragile!

https://forum.chasedream.com/thread-614546-1-1.html

billyisfragile!

是原文吗？

【文章大意】
1.        介绍了一下说很多人认为有火山的地方容易找到铜矿。（第一段几乎没有用）
2.        但是没有直接的证据证明。要证明有关系需要有indirectly evidence来support。2个。
火山口的某种细菌是一种证明。远古的时候细菌随着地壳变动最后变成了bodies。而且现在的火山里面也可以找到这种细菌。 （有个题目问这个，要特别注意细菌的bodies和细菌的区别） ----这个理由好奇怪，自己确认
3.        第一个和某某种石头有关而这种石头的形状说明是从地壳运动中挤压出来 的。。。
4.        第二个是说目前的矿石源大都集中在一些sea ridge，而这些sea ridge是传统的火山多发带，提到copper在地下形成管状的pipe，处于地震多发带
【题目】
1.        第一个证据里面提到的石头的形状说明了什么问题？: 选了形成铜矿和火山之间联系
2.        这里有道题是问作者的态度的，我选了作者同意铜矿和火山的联系，但是找到直接证据，而是间接的证据
3.        有题，针对尾端：答可以infer到这种铜矿是形成在火山带
4.        indirect的evidence其中提到有个an opening of earth surface 有题：不能说明关系

A volcanic origin?

From the foregoing discussion, it is apparent that porphyry copper deposits came into being as a result of special geological conditions. Much evidence has now been accumulated that leads us to suspect that the deposits were formed as lay-products of volcanic activity where deep-seated magma bodies had suitable compositions and properties and where crustal characteristics permitted those bodies to rise rapidly to shallower levels. The evidence is indirect, and hence inconclusive, however, because the volcanic structures that may once have existed above the deposits would have been topographically and compositionally unstable and thus would have been removed rapidly by weathering, and because a large percentage of known deposits are now exposed as a result of millions or tens of millions of years of erosion.

Nevertheless, a volcanic origin for many porphyry copper deposits is consistent with the following facts. First, by far the greatest number of deposits are of Mesozoic age or younger—less about 230 million years old—and are located in either the “ring of fire,“ the belt of volcanoes and volcanic rocks that encircles the Pacific Ocean, or the “Tethyan” belt, the east-west band of volcanic rocks and mountains that extends throughout the southern Soviet Union and into the Middle East (Fig. 5). The association of the deposits with volcanic rocks and the style of occurrence are much the same in both regions. Moreover, both these parts of the world are currently the sites of much earthquake activity and volcanism, which are believed to be manifestations of the same sorts of events as are known to have occurred in or near these regions ever since about 230 million years ago.

Second, although most of the rocks that existed at the time the ore was formed have been removed by erosion. there are a few deposits where remnants of volcanic rocks about the same-age as the porphyries (up to 200 million years old) are found, and where porphyries containing copper deposits are present as intrusions in the volcanic rocks (Fig. 6). This coincidence of porphyries and volcanic rocks in both time and space is strong evidence for a volcanic origin for the deposits.

Third, the theory of the origin of porphyritic textures described previously involves two stages of cooling: an early stage, during which crystals of silicate minerals started to form, and a late stage, in which the residual magma was quenched to form a fine-grained matrix. The late stage of cooling was thought to be the result of magma rising rapidly to the cooler environment of the shallow crust. According to the volcanic genesis theory, the porphyry intrusions, which have compositions similar to those of many volcanic rocks, formed when magma rose rapidly toward the earth’s surface through the core of a volcano.

4.        indirect的evidence其中提到有个an opening of earth surface 有题：不能说明关系

Fourth, a large percentage of porphyry copper deposits contain bodies of breech—angular fragments of rock, which, in some instances, are cemented with fine crystalline volcanic-like rock or with rock “flour" derived from the mutual abrasion of porphyry fragments (Fig. 2). Such bodies are commonly irregular, essentially vertical columns, or “pipes,” with round or elliptical cross sections; less commonly, they assume a tabular form, such as that of a vertical sheet, or “dike.” The transportation and pulverization of rocks in breccias, as well as the geometry of the breccia bodies, suggest that there may have been an opening to the surface at the time that they formed. Moreover, breccias that look like these are present in active volcanic systems, where openings clearly exist.

Fifth, the distribution of deposits in well-explored regions of the Pacific rim shows tendencies toward clustering, as in southwest North America. where clusters occur in areas about 30 km by 30km (Fig. 7), and toward formation along lines on the earth's surface, as in the Andes. Volcanoes show similar tendencies to cluster or form along lines. This similarity in distribution of volcanic centers and porphyry ore deposits is not in itself compelling evidence for an association, but taken together with the other pieces of evidence, it strengthens the case.

The inferred link between circum-Pacific volcanism and the formation of porphyry ore deposits is extremely important, because it establishes a rational basis for searching for such deposits. Moreover, the high success rate—the discovery of more than a hundred new deposits—over the past two decades of searching premised in part on the assumption that the theory is correct attests in some measure to its validity.

shdklnalfnldakn

楼主 我可以问下你的阅读jj是哪里看到的吗

Hanxi321

BOYisme 发表于 2018-8-21 23:29
数学：
1. 2/A66
2. E

第二题为什么不是B呀？新加的3个数的中位数不是78，是不是就可以确定combined series的中位数不是78了呢？