标题: og12-69 [打印本页] 作者: liverpool123 时间: 2010-1-1 22:19 标题: og12-69 Scientists have modifi ed feed corn genetically, increasing its resistance to insect pests. Farmers who tried out the genetically modifi ed corn last season applied less insecticide to their corn fi elds and still got yields comparable to those they would have gotten with ordinary corn. Ordinary corn seed, however, costs less, and what these farmers saved on insecticide rarely exceeded their extra costs for seed. Therefore, for most feed-corn farmers, switching to genetically modifi ed seed would be unlikely to increase profi ts. Which of the following would it be most useful to know in order to evaluate the argument? (A) Whether there are insect pests that sometimes reduce feed-corn yields, but against which commonly used insecticides and the genetic modifi cation are equally ineffective (B) Whether the price that farmers receive for feed corn has remained steady over the past few years (C) Whether the insecticides typically used on feed corn tend to be more expensive than insecticides typically used on other crops (D) Whether most of the farmers who tried the genetically modifi ed corn last season applied more insecticide than was actually necessary (E) Whether, for most farmers who plant feed corn, it is their most profi table crop
答案D把原文的Farmers who tried out the genetically modifi ed corn last season applied less insecticide 质疑了下，既然是原文都说了，再去质疑对吧？
一般evaluation结论的题目可以这样吗？
大部分是不是应该找到结论和前提之间的空白来质疑呢？作者: SMcollapse 时间: 2010-3-6 22:59
同问啊，今天做到这题也没看懂答案 题目不是已经说了， Farmers who tried out the genetically modified corn last season applied less insecticide to their corn fields and still got yields comparable to those they would have gotten with ordinary corn. 为什么答案还有说花更多的钱在杀虫剂上面啊？？ 牛牛们解释一下啊作者: jhhuzhle 时间: 2010-3-7 00:14
我也做错了。。看了后自己是这样想的，主要条件：改基因谷子用的杀虫剂少，但是价钱贵。 普通谷子便宜，杀虫剂多了点。 附加条件：杀虫剂其实很便宜 。两种谷子产量相近。