数学：

1 数列求和公式Sn=n(n+1)，a3=?

解答：很简单 求出S3和S2，S3-S2=a3

2 还有一个数列题，告诉了前两项（具体数字不记得了），说从第三项开始，每一项都是前面所有项的和，问得是a24/a20。

解答：这个数列后面就是一个公比为2的等比数列了，因此a24/a20=16

3）DS题，是一个集合题，告诉你一共40人，做A（已经抽象化了）的是15人，做B的是12人，求得是既不作A，又不作B的人数

1、A和B都做的人是10人

2、只做A和只做B和A和B都作的一共是17人

我选的是D

4) DS提，就是那道火车相遇时，那一辆到目的地更近 （前面的jj中有）

5）告诉你一个点的坐标，求该点到Y轴的距离。暴简单。

6）直角等腰三角形的面积已知，求周长。

RC 有一篇GWD中的原文（我的第一篇文章）

In American Genesis, which covers

the century of technological innovation

in the United States beginning in 1876,

Line                     Thomas Hughes assigns special promi-

(5)                 nence to Thomas Edison as archetype

of the independent nineteenth-century

inventor. However, Hughes virtually

ignores Edison’s famous contem-

porary and notorious adversary in

(10)               the field of electric light and power,

George Westinghouse. This com-

parative neglect of Westinghouse is

consistent with other recent historians’

works, although it marks an intriguing

(15)               departure from the prevailing view

during the inventors’ lifetimes (and for

decades afterward) of Edison and

Westinghouse as the two “pioneer

innovators ” of the electrical industry.

(20)                             My recent reevaluation of Westing-

house, facilitated by materials found

in railroad archives, suggests that

while Westinghouse and Edison shared

important traits as inventors, they

(25)               differed markedly in their approach to

the business aspects of innovation.

For Edison as an inventor, novelty

was always paramount: the overriding

goal of the business of innovation was

(30)               simply to generate funding for new

inventions. Edison therefore undertook

just enough sales, product development,

and manufacturing to accomplish this.

Westinghouse, however, shared the

(35)               attitudes of the railroads and other

industries for whom he developed

innovations: product development

standardization, system and order

were top priorities. Westinghouse

(40)               thus better exemplifies the systematic

approach to technological development

that would become a hallmark of modern

corporate research and development.

有一个是好像是原题：

The primary purpose of the passage is to

1. reevaluate a controversial theory
2. identify the flaws in a study
3. propose a new method of historical research
4. compare two contrasting analyses
5. provide a fresh perspective （E）

还有一个题目是问与George Westinghouse同时代的人是怎么评价George Westinghouse的？

还有一个题目实在想不起来了。

SC，碰到了一道争议题：