ChaseDream

标题: gwd19 [打印本页]

作者: lykuang02 时间: 2005-11-9 12:47
标题: gwd19

Q20:

Which of the following most logically completes the reasoning?

Either food scarcity or excessive hunting can threaten a population of animals. If the group faces food scarcity, individuals in the group will reach reproductive maturity later than otherwise. If the group faces excessive hunting, individuals that reach reproductive maturity earlier will come to predominate. Therefore, it should be possible to determine whether prehistoric mastodons became extinct because of food scarcity or human hunting, since there are fossilized mastodon remains from both before and after mastodon populations declined, and ______.

there are more fossilized mastodon remains from the period before mastodon populations began to decline than from after that period

the average age at which mastodons from a given period reached reproductive maturity can be established from their fossilized remains

it can be accurately estimated from fossilized remains when mastodons became extinct

it is not known when humans first began hunting mastodons

climate changes may have gradually reduced the food available to mastodons

Answer: B

Q40:

Agricultural societies cannot exist without staple crops. Several food plants, such as kola and okra, are known to have been domesticated in western Africa, but they are all supplemental, not staple, foods. All the recorded staple crops grown in western Africa were introduced from elsewhere, beginning, at some unknown date, with rice and yams. Therefore, discovering when rice and yams were introduced into western Africa would establish the earliest date at which agricultural societies could have arisen there.

Which of the following is an assumption on which the argument depends?

People in western Africa did not develop staple crops that they stopped cultivating once rice and yams were introduced.

There are no plants native to western Africa that, if domesticated, could serve as staple food crops.

Rice and yams were grown as staple crops by the earliest agricultural societies outside of western Africa.

Kola and okra are better suited to growing conditions in western Africa than domesticated rice and yams are.

Kola and okra were domesticated in western Africa before rice and yams were introduced there.

Answer: A

作者: lykuang02 时间: 2005-11-9 12:49

As to Q20, I can not make clear the key.

As to Q40, could you translation words of A to Chinese for me?

Thanks a lot.

作者: shaoji 时间: 2006-1-6 00:20

20:文中通过化石判断灭古象的灭绝原因要么是因为食物短缺(象就会推迟生理成熟,人口少,吃的饱),要嘛是过渡狩猎(象会提早成熟,多生Baby).所以只要化石能提供生理成熟年龄就知道灭绝原因了.B提供了答案

40:农业社会不能脱离主粮,虽然一些水果植物是西非人民的美食,但是它们只是辅助性的,不是主食.而记载中西非人民的主食大米芋头都是其他地方引进的,但是具体时间不清楚.因此了解了啥时候西非引进大米和洋芋就可以知道西非农业社会的建立时间了.前提是西非人民在引进大米之前不发展主食

欢迎光临 ChaseDream (https://forum.chasedream.com/)