80．很多厂不仅自己开发自己品牌的商品
而且还生产零售商private brand的商品。这是很令人惊奇的，因为这些商品不仅和厂的商品竞争，marginal revenue of the retailer也远远比厂高。问account for the fact as suprising. 好吧
我觉得每一个选项能选，折磨在前面的题目花了很长时间。。。后面就有些来不及瞎选了。。。。
我好像遇到2道基金就是关于公路上prey的，还有一道关于图书馆保护书是否带手套神马的（大家可以参考一下之前的寂静）
81.说有些人有eye disorder（反正就是眼睛不好），看太亮的光看不出，因为这些人的r 细胞对太亮的光的神马东西敏感，但是看dim的光可以，因为r细胞对dim的光不敏感，然后问conclusion
我选了：如果制作一种眼镜，tranparent to 神马，过滤神马，可以帮助他们（我知道我写的狗p不通，不过当时满清晰觉得是选这个。。。）
考古81
GWD原题（待确认）
GWD-11-Q31: People with a certain eye disorder are virtually unable to see in moderately bright light, which seems to them unbearably intense, since the cells of their retinas are overwhelmed by moderately bright light. These people do, however, show normal sensitivity to most components of dim light. Their retinal cells are also not excessively sensitive to red components of moderately bright light.
The information above best supports which of the following hypotheses about people with the disorder described, if they have no other serious visual problems?
A. In all moderately dim light in which people without the disorder can read large print, people with the disorder cannot read such print.
B. In an otherwise darkened concert hall, these people will see a dimly illuminated red exit sign more clearly than small dim white lights that mark the aisles.
C. These people typically see more acutely at night and in dim light than do most people who do not have the disorder.
D. Eyeglasses that are transparent to red components of light but filter out other components of light help these people see in moderately bright light. （Answer）
E. These people perceive colors other than red in the same way as do most people who do not have the disorder.
