问两道逻辑题

miguel29

Rabbits were introduced to Numa Island in the nineteeth century. Overgrazing by the enormous population of rabbits now menaces the island's agriculture. The government proposes to reduce the population by using a virus that has caused davastating epidemics in rebbit populations elsewhere. There is, however, a chance that virus will infect the bilby, an endangered native marsupial. The government's plan, therefore, may serve the interests of agriculture but will clearly increase the threat to native wildlife.

Which of the following , if true, most seriously weakens the arguement?
答案：Overgrazing by rabbit endangers many of the plants on which bibies feed.
我选 There are no species of animals on the island that prey on the rabbits.
我觉得题干不是说wildlife吗？所以我感觉这个选项好像更贴切些吧？


In the past, every ten-percentage-point increase in cigarette prices in the country of Coponia has decreased per captia sales of cigarettes by four percent. Coponia is about to raise taxes on cigarettes by 9 cents per pack. The average price of cigarettes in Coponia is and has been for more than a year 90 cents per pack. So the tax hike stands an excellent chance of reducing per captia saless of cigarettes by four percent.

Which of following is an assumption to which the arguement depends?
答案：Tobacco companies are unlikely to reduce their profit per pack of cigarettes to aviod an increase in the cost per pack to consumers in Copnia.
想不通，我取了非，也没发现它削弱结论啊？

子夜风衍

先说第一题 明显是无关选项 问削弱
题的逻辑是 不能用virus 因为virus 对bilby （native wildlife一回事）有害

子夜风衍

第二题 常识 如果顾客买烟的钱 = price+tax
如果政府加tax而Tobacco companies把price降了（reduce their profit）
那么顾客买烟的钱就不变了

miguel29

谢谢啦，数学型逻辑题让我很无奈