OG Diagnostic Test 两道非常晕的逻辑题，求解释！！！

dydxxl

34.  A year ago, Dietz Foods launched a yearlong
advertising campaign for its canned tuna. Last year
Dietz sold 12 million cans of tuna compared to the 10
million sold during the previous year, an increase
directly attributable to new customers brought in by
the campaign. Profits from the additional sales,
however, were substantially less than the cost of the
advertising campaign. Clearly, therefore, the campaign
did nothing to further Dietz’s economic interests.
Which of the following, if true, most seriously weakens
the argument?

(A) Sales of canned tuna account for a relatively
small percentage of Dietz Foods’ profits.

(B) Most of the people who bought Dietz’s canned
tuna for the first time as a result of the
campaign were already loyal customers of other
Dietz products.

(C) A less expensive advertising campaign would
have brought in significantly fewer new
customers for Dietz’s canned tuna than did the
campaign Dietz Foods launched last year.

(D) Dietz made money on sales of canned tuna last
year.

(E) In each of the past five years, there was a steep,
industry-wide decline in sales of canned tuna.

正确答案选E，我选了B。

首先说E，我没看出来E和问题有什么关系。看过一些人的解释，说E的意思是因为整个行业的sales 有一个decline，但是通过advertising campaign, Dietz公司的的销量却上涨了，说明这个advertising是有作用的。

但是我认为题目文章的结论（clearly, therefore, the campaign did nothing to further Dietz's economic interests）不是在说这个advertising campaign到底好不好，而是说因为做这个campaign的cost要大于它所带来的收入，即cost>additional benefit，所以在经济收入上没有给Dietz带来economic interests。E选项中，即使说Campaign使得Dietz在同行业sales下降的时候获得了上升的sales，对cost>benefit，然后economic interest<0这个事实没有任何作用。

相反，看B选项，我的理解是虽然campaign在这次带来的收益只有12million-10million=2million of cans，这个additional benefits小于campaign的cost,但是，如果根据B选项，这次campaign中增加的顾客在之后就变成了Dietz的忠实顾客，也就是说在以后的几年中，这些增加的顾客会还买Dietz的产品，campaign带来的收益不只停留在一年，也不仅限于买canned tuna带来的收益。今后的几年里还有持续additional benefits。这样additional benefits 就不一定小于cost了，从而削弱结论。

有人解释说B之所以错是因为B有一个"were already".意思是这这些顾客本来就是loyal customers，而非campaign带来的。但是这句话"most of the people who bought Dietz's canned tuna for the first time as a result of the campaign were already loyal customers of other Dietz products",可不可以理解成这些因为campaign带来的第一次买canned tuna的顾客已经成为了Dietz的忠实顾客（买了第一次canned tunna之后变成了忠实顾客）？

25. 25. Tiger beetles are such fast runners that they can capture virtually any nonflying insect. However, when running toward an
insect, a tiger beetle will intermittently stop and then, a moment later, resume its attack. Perhaps the beetles cannot
maintain their pace and must pause for a moment’s rest; but an alternative hypothesis is that while running, tiger beetles
are unable to adequately process the resulting rapidly changing visual information and so quickly go blind and stop.
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two
hypotheses and undermine the other?

(A) When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately stops and runs away without its usual intermittent stopping.

(B) In pursuing a swerving insect, a beetle alters its course while running and its pauses become more frequent as thechase progresses.

(C) In pursuing a moving insect, a beetle usually responds immediately to changes in the insect’s direction, and it pauses equally frequently whether the chase is up or down an incline.

(D) If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.

(E) The faster a beetle pursues an insect fleeing directly away from it, the
more frequently the beetle stops.

这道题我在BC之间犹豫，正确答案选B。

借用OG的分析，两种假设，第一种是tiredness要停，第二种是因为vision问题要停。

首先B选项。OG给出的解释是B选项加强了第二种假设。首先B选项中说在追一个swerving insect的时候，beetle会alter its course. 这一部分与pause无关，不能加强第二种假设。后半部分“and its pauses become more frequent as the chase progresses”，我不明白这部分是想说明什么，如果说被追的insect改变方向的frequency增加，然后beetles pauses的frequenc也随之增加，还能说明跟第二个假设有关系，选项中之说beetles pauses的频率在追逐过程中增加，并没有说insect改变方向上的变化。

即使，勉强能加强第二个假设，那跟第一个假设有什么关系？不是说选项既要加强一个，又要削弱另一个才可以吗？

C选项，其实我觉得也有很大问题。。。虽然我选了它。。但是OG的解释不理解。OG说C选项跟两种假设都没有关系，跟tiredness无关，也跟vision无关。最起码它说in pursuing a moving insect, a beetle usually responds immediately to changes in the insect's direction.不是能说明beetle在insects转变方向的时候不用停顿，也就是说vision是没有问题的，也就削弱了第二个假设不是吗。。求解释，怎么会无关呢？

本人有时候分析爱钻牛角尖，望高人指点啊~~

Jed0079

顶！ 同问！

xiaoyanjoy

顶！为什么就没人来回答呢？我也不太明白这俩题

sdcar2010

34. The conclusion is: the campaign did NOTHING to further Dietz’s economic interests.

If a campaign did SOMETHING to further Dietz's economic interests, then the conclusion is weakened. E) says that the campaign minimized the loss. That's SOMETHING!

B) on the other hand states that those NEWLY added buyers of the can were loyal customers to begin with. Therefore, it is likely, these customer bought the item out of blind loyalty rather than affected by the AD CAMPAIGN. In other words, the AD CAMPAIGN has no effect to lure NEW customers. B) strengthens the conclusion. The campaign did NOTHING. The phrase "as a result" does not suggest any causation between the two items. It only indicates correlation. For the record, those buyers might not have watched those AD.

oooga0127

25 当Insect是活动的时候，B,C都已经说明,tiger beetle会向着insect移动的方向行动，说明tiger beetle的停顿不是因为眼睛看不见。这样第二个假设就否定掉了。现在要支持第一个假设。
看B,C的后半句。B：当tiger beetle不停追赶insect的时候，停顿更加频繁。 C：不管tiger beetle对insect的追赶是加快还是减慢，停顿的频率都是一样的。显然，B能够支持第一个假设。。。
额，不知道对不对

AngelEyre

顶！！！为什么没有进一步解释呢？感觉OG的解释明显不通啊。。。

chenqian7261

如果B选项是削弱结论的，那么B取非则加强或者对结论无影响。B取非是“第一次来买的顾客不是公司的忠实顾客。”恰好说明campaign 是对公司经济有帮助的。这才是削弱了作者的结论，所以B选项就不是真正的削弱、


第二题：B选项说 tiger beetles 会随着insect迂回的过程而不断停止，削弱因为累的可能性，加强是因为会blind的可能性、C选项说beetles可以立刻转换方向。削弱是blind的可能性，但是因为追逐速度的up and down，beetles会equally pause。则是加强blind的可能性。选项C矛盾而且和the first assumption 无关、

cadylql

c反对两者。首先反对hypo2很清楚因为beetles对变化反应快。然后反对hypo1是因为常理是上坡容易累要多休息而下坡反之，但是这个beetles上下坡pause频率一样，说明pause和rest无关