gwd -17-11有对应的讨论连接吗?

Matrixrl

有的话给请哪位告诉我一下,没的话请帮忙解释一下

Some species of Arctic birds are threatened by recent sharp increases in the population of snow geese, which breed in the Arctic and are displacing birds of less vigorous species.  Although snow geese are a popular quarry for hunters in the southern regions where they winter, the hunting season ends if and when hunting has reduced the population by five percent, according to official estimates.  Clearly, dropping this restriction would allow the other species to recover.

 

Which of the following, if true, most seriously undermines the argument?

 

1. Hunting limits for snow geese were imposed many years ago in response to a sharp decline in the population of snow geese.
2. It has been many years since the restriction led to the hunting season for snow geese being closed earlier than the scheduled date.
3. The number of snow geese taken by hunters each year has grown every year for several years.
4. As their population has increased, snow geese have recolonized wintering grounds that they had not used for several seasons.
5. In the snow goose’s winter habitats, the goose faces no significant natural predation.

答案是B

晴天小狗

直接搜索 17-11

这道题我看了1小时了 还没明白

郁闷中...

Matrixrl

知道了,谢谢

Matrixrl

这题我懂了,其实也满简单的:

雪鹅威胁其他物种并且规定打猎数量超过5%则打猎季节结束

结论:取消规定可增加其他物种数量

B.由于此规定而导致打猎季节提前结束的情况已经好多年未出现了,这说明最近这些年来猎人一直打不到5%的规定数量,那么这个规定就不起作用,所以取不取消并不影响其他物种数量,从而削弱结论

晴天小狗

没错：

原文：取消狩猎5%的限制就会帮助鸟儿们，即猎人会杀死更多的鹅仔

B：狩猎期已经有很多年没有比预定的日期提前结束了，即hunters打猎比以前要少了，也就是每次都实际达不到5%。

但是，如果狩猎期限取消，即regulation取消，猎人们就可以继续狩猎了，这样就可以杀死更多的geese啊？

我哪里出问题了？ 请指点！...

Matrixrl

应该这样理解,即使取消了规定也没用,因为不取消都打不到5%,所以取消不会增加整个冬季的猎杀量

晴天小狗

恩，思路其实很明显

那么这里需要假设：不管有没有限制，只要过了期限，猎人就不会打猎...

Matrixrl

应该说是在冬季打猎,有规定的话打到一定份额就早结束,否则就贯穿整个冬季

估计和其他季节无关,否则那群鹅连一个季度都别想活下来了,早就被屠光了

晴天小狗

所以还是有gap。 很是郁闷

谢谢 哈

Matrixrl

它只说了打猎在冬季,我们也不好自己乱猜,只好根据已知的推