gwd1-30

pxx105

    

Q30:

    

The quality of unrefined olive oil is not actually defined
in terms of acidity, yet extensive tests have shown that the less free oleic
acid an unrefined olive oil contains per liter, the higher its quality.  The proportion of free oleic acid that an olive
oil contains is an accurate measure of the oil’s acidity.

    

 

    

If the statements above are all true, which of the following
conclusions is best supported by them ?

    

 

    

1. When
        an olive oil is refined, the concentration of oleic acid in the oil is
        reduced.
2. The
        quality of an unrefined olive oil can be determined only by accurately
        measuring its acidity.
3. If an
        unrefined olive oil is intermediate in acidity between two other unrefined
        olive oils, it will also be intermediate between them in quality.
4. Free
        oleic acid is the only acid that unrefined olive oil contains.
5. People
        who judge the quality of unrefined olive oils actually judge those oils by
        their acidity, which the judges can taste.

    

  
Answer:

Anwer isB. But why?

easttiger

I guess you should have confusion in C. However, C can be true only assuming a linearity between acidity of the oil and the proportion of the oleic acid in the oil. However, this linearity is not implied in the original text which states only to the extent of measurability, not how it will be measured. After all, other nonlinear relationship, such as a quadratic one, between the proportion of oleic acid and the acidity can suffice an accurate measurement.

B is true. If you can use property A to measure, accurately, property B, you can do the reverse-although it is posible that the reverse may not give you a single outcome, it nevertheless will be a measurement, and the outcomes will all be accurate.

pxx105

Sorry, Easttiger, I gave the wrong answer. The answer should be C instead of B.

easttiger

Then you can critique my argument for whatever unsupported assumtion it contains, then reverse the conclusion infavor of C.

[此贴子已经被作者于2008-8-8 0:39:58编辑过]

yi11

我选(C)

(B)因为有determined ONLY所以scope变化不对。而且文章只说油的质量没有用酸度定义，并没有说有没有别的方法可以测出油质或者优质可以用酸度以外的维度衡量。

(C)没有说酸度和质量一定是线性关系，但是是不是线性全系不影响文章推理。文章仅仅说是酸度越少质量越高，所有满足这个关系的都有可能（）。由此如果X,Y,Z酸度从低到高，Y的质量一定是在X和Y中间。

(A)(D)(E)因为有无关概念能够快速排除