论说文：根据下述材料，写一篇700字左右的论说文，题目自拟。 无人车作为一种新兴技术，正在如火如茶地发展。在《纽约时报》最新获取的Uber内部报告中显示：前段时间出现的无人车撞死人事故

设等差数列{an}和{bn}的前n项和分别为Sn、Tn，且，则=______。 A． B． C． D． E．无法确定

某人5次上班途中所花的时间(单位：min)分别为x，y，10，11

关于x的方程lg2x-algx+1=0的解都大于1，则a的取值范围是______。

若不等式ax2+bx+c＞0的解为，则不等式cx2+bx+a＜0的解为______。 A． B．x＜-3或 C． D．x＜-2或 E．

一个车队以4米/秒的速度缓缓通过一座长200米的大桥，共用115秒．已知每辆车长5米

等式|2a-1|=|3a+5|-|a+6|成立，则实数a的取值范围为______． A． B．(-1，+∞) C． D． E．

一项工程由甲、乙两队一起做30天可以完成，甲单独做24天后，乙队加入，两队一起做10天后

若不等式的解集为{x|m≤x≤n，且|m-n|=2a}，则a的值为

若f(x)=3x3-kx2+4被3x-1除以后余数为3，则k=______．

在3和2187之间插入若干个正数，使它们组成等比数列，若插入的这些数的和是1089

甲从1、2、3中抽取一个数，记为a；乙从1、2、3、4中抽取一数，记为b，规定当a＞b或者a+1＜b时甲获胜，则甲取胜的概率为______。 A． B． C． D． E．

从集合{0，1，3，5，7}中先任取一个数记为a，放回集合后再任取一个数记为6，若ax+by=0能表示一条直线，则该直线的斜率等于-1的概率是______． A． B． C． D． E．

若实数x，y满足等式(x-2)2+y2=3，则的最大值是 A． B． C． D． E．1

甲、乙两人同时从A地出发，沿400米跑道同向匀速行走

三人分糖，每人都得整数块，乙比丙多得13块，甲所得块数是乙的2倍

一列火车长75米，通过525米长的桥梁需要40秒，若以同样的速度穿过300米的隧道

It is curious that Stephen Koziatek feels almost as though he has to justify his efforts to give his students a better future. Mr. Koziatek is part of something pioneering. He is a teacher at a NewHampshire high school where learning is not something of books and tests and mechanical memorization, but practical. When did it become accepted wisdom that students should be able to name the 13th president of the United States but be utterly overwhelmed by a broken bike chain? As Koziatek knows, there is learning in just about everything. Nothing is necessarily gained by forcing students to learn geometry at a graffitied desk stuck with generations of discarded chewing gum. They can also learn geometry by assembling a bicycle. But he's also found a kind of insidious prejudice. Working with your hands is seen as almost a mark of inferiority. Schools in the family of vocational education "have that stereotype...that it's for kids who can't make it academically," he says. On one hand, that viewpoint is a logical product of America's evolution. Manufacturing is not the economic engine that it once was. The job security that the US economy once offered to high school graduates has largely evaporated. More education is the new principle. We want more for our kids, and rigitfully so. But the headlong push into bachelor's degrees for all—and the subtle devaluing of anything less—misses an important point: That's not the only thing the American economy needs. Yes, a bachelor's degree opens more doors. But even now, 54 percent of the jobs in the country are middle-skill jobs, such as construction and high-skill manufacturing. But only 44 percent of workers are adequately trained. In other words, at a time when the working class has turned the country on its political head, frustrated that the opportunity that once defined America is vanishing, one obvious solution is staring us in the face. There is a gap in working-class jobs, but the workers who need those jobs most aren't equipped to do them. Koziatek's Manchester School of Technology High School is trying to fill that gap. Koziatek's school is a wake-up call. When education becomes one-size-fits-all, it risks over-looking a nation's diversity of gifts. A broken bike chain is mentioned to show students' lack of ______.

已知D是由不等式组所确定的平面区域，则x2+y2=4在区域。内的弧长为______。 A． B． C． D． E．

设甲、乙两个圆柱的底面面积分别为S1、S2，体积为V1、V2若它们的侧面积相等且，则______． A．1 B． C． D． E．以上都不正确