文章：According to many analysts, labor-management relations in the United States are undergoing a fundamental change: traditional adversarialism is giving way to a new cooperative relationship between the two sides and even to concessions from labor. These analysts say the twin shocks of nonunion competition in this country and low-cost, high-quality imports from abroad are forcing unions to look more favorably at a variety of management demands: the need for wage restraint and reduced benefits as well as the abolition of "rigid" work rules, seniority rights, and job classifications. Sophisticated proponents of these new developments cast their observations in a prolabor light. n return for their concessions, they point out, some unions have bargained for profit sharing, retraining rights, and job--security guarantees. Unions can also trade concessions for more say on the shop floor, where techniques such as quality circles and quality-of-work­ life programs promise workers greater control over their own jobs. Unions may even win a voice in investment and pricing strategy, plant location, and other major corporate policy decisions previously reserved to management. Opponents of these concessions from labor argue that such concessions do not save jobs, but either prolong the agony of dying plants or finance the plant relocations that employers had intended anyway. Companies make investment decisions to fit their strategic plans and their profit objectives, opponents point out, and labor costs are usually just a small factor in the equation. Moreover, unrestrained by either loyalty to their work force or political or legislative constraints on their mobility, the companies eventually cut and run, concessions or no concessions. Wage-related concessions have come under particular attack, since opponents believe that high union wages underlay much of the success of United States industry in this century. They point out that a long-standing principle, shared by both management and labor, has been that workers should earn wages that give them the income they need to buy what they make. Moreover, high wages have given workers the buying power to propel the economy forward. f proposals for pay cuts, two-tier wage systems, and subminimum wages for young workers continue to gain credence, opponents believe the U.S. social structure will move toward that of a less-developed nation: a small group of wealthy investors, a sizable but still minority bloc of elite professionals and highly skilled employees, and a huge mass of marginal workers and unskilled laborers. Further, they argue that if unions willingly engage in concession bargaining on the false grounds that labor costs are the source of a company's problems, unions will find themselves competing with Third World pay levels-a competition they cannot win. 想请问郭老师，这题opponents观点是在第三段，但是原文和选项要怎么对照呢...怎么从观点看出态度？

如果n是19的话n+1才是20。那a20不是应该等于a19+19吗，为什么会加20呢？条件二给的公式不是说a(n+1)=a(n)+n吗？我算的是1+2+...+19+19这样

@陆旭老师 第39题要怎么做呢？

@唐小梅老师 这道题用您的方法咋做呀？

@英吉老师 第715题的b选项为啥不算说了原文解释的对立面。是不是因为它主要讲的是electricity不是fossil fuel？ e选项这个地方算是要知道的常识吗？因为当时排除掉e选项就是因为自己脑袋里根本没有这个概念，感觉与原文无关。但是一旦听你说了，接受了说这个设定我是能理解的。所以以后再碰到这种不确定的情况，就默认判定这个选项是可行的，然后再去结合文章看是否支持原文逻辑链吗？

@陆旭老师 当出现overlapping info时，应该用matrix比较好还是用韦恩图比较好？

@英吉老师 如果这道题选了a，算是犯了什么错误？

请问老师这道题是不是答案给错了？不应该是4+8+12+...+200求和吗

想问一下小梅老师这道题的思路

想问一下小梅老师这道题如何快速得出答案？感觉自己解题思路有问题 2分钟内无法解答 类似题有没有什么快速切入的技巧？

A为什么不行？