问题 单项选择题

The facts show that the fear of flying in airplanes is not rational. In 1986 alone, there were 46,000 fatalities in highway accidents, but from 1980 to the present an average of only 77 per year in accidents on major domestic airlines. The rate for regional airlines was only slightly higher.
If the evidence cited above is accurate, which of the following would be most important to know in order to evaluate the force of that evidence

A.Whether repeated airplane travel allays fear of flying in airplanes.

B.Whether regional and domestic airlines spend the same average amount of time per aircraft on maintenance.

C.How many people reported a fear of flying in airplanes that was p enough to prevent them from traveling by air.

D.How many people per year have traveled by highway and how many by air since 1980.

E.(E) How much higher the accident rate has been for regional airlines than for major domestic airlines since 1980.

答案

参考答案:D

单项选择题

根据近20年来的详细调查,海洋里的动物大约有18万种,植物约2万种。这些丰富的海洋生物可为人类社会提供食物、药物和工业原料。其中已被人类开发利用的经济价值较大的鱼类400多种,贝类和甲壳类近百种,藻类70多种,仅占海洋生物种属的一小部分。目前,这些野生海产品的年捕捞量可达2亿吨以上,大约可生产2000多万吨蛋白质食品,对缓解人类食品短缺和补充人体营养起着举足轻重的作用。近几年来,在南北极的科学考察发现,极区海域的渔业资源极为丰富,特别是南极海域的磷虾资源,如加以合理开发,每年可捕捞近亿吨。更令人惊喜的是,近年来的深海考察发现,一直被认为是生命极限区(水深600米以下)的深海底也有生物存在,海洋里的生物资源目前难以估量,其开发前景十分广阔。
随着海洋科学技术的不断发展,80年代兴起的“海上牧场”,已经给人类的食物源带来了生机。据统计,1995年全世界共放牧了100亿尾海洋经济鱼,回捕量已达到1000多万吨。而目前放养的经济贝类,回捕量更是高得惊人,浅海网箱养殖业也正在蓬勃发展,并获得了好收成。海上人工养殖逐步走上了正轨,人类已从海上“猎人”转业为海上“牧民”,耕海牧鱼是21世纪的一大产业

野生海产品对缓解人类食品短缺和补充人体营养:

A.作用不大
B.有点作用
C.没有作用
D.举足轻重

问答题 简答题