Knewton CR - good one

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Knewton CR - good one

by Deepthi Subbu » Mon Sep 05, 2011 4:25 am
A new technique for extracting ethanol, an alternative heat and fuel source, from corn, uses stover, which is a byproduct of wheat farming. This technique is profitable as long as petroleum prices stay above $2.00 per gallon and corn prices remain under $3.00 per bushel. Since petroleum prices have not dropped below $2.00 per gallon in several years, and corn prices are now at $3.50 per bushel and projected to fall in the future, anyone wishing to invest in companies with the potential for rapid growth in profits would be well-advised to invest in wheat farms, whose currently nearly worthless product will soon become a valuable commodity.

Which of the following, if true, most seriously weakens the argument above?


(A) A small quantity of stover is currently sold to nuclear energy plants, but the vast majority of it is discarded as bio-waste.

(B) The $3.00 per bushel maximum corn price as a threshold of profitability accounts for the extra costs of separating stover from other corn byproducts and converting it to ethanol.

(C) Only sixty percent of the potential ethanol in any given stalk of corn can be extracted using conventional techniques of ethyl hydration or yeast fermentation.

(D) Techniques to extract ethanol from corn that do not rely on stover require significantly more petroleum-derived energy and, as such, become less profitable when petroleum prices rise above two dollars per gallon.

(E) The quantity of stover produced annually as a byproduct of wheat farming is several times the amount that is likely to be useful in the production of ethanol.

OA to follow

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by cans » Mon Sep 05, 2011 4:31 am
OA E
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by Deepthi Subbu » Mon Sep 05, 2011 5:32 am
Cans, can you explain pls?

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by lazymonster » Mon Sep 05, 2011 5:36 am
i go for option d.pls tell me whether i m right or wrong.

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by prashant.mishra » Mon Sep 05, 2011 5:44 am
A new technique for extracting ethanol, an alternative heat and fuel source, from corn, uses stover, which is a byproduct of wheat farming. This technique is profitable as long as petroleum prices stay above $2.00 per gallon and corn prices remain under $3.00 per bushel. Since petroleum prices have not dropped below $2.00 per gallon in several years, and corn prices are now at $3.50 per bushel and projected to fall in the future, anyone wishing to invest in companies with the potential for rapid growth in profits would be well-advised to invest in wheat farms, whose currently nearly worthless product will soon become a valuable commodity.

Which of the following, if true, most seriously weakens the argument above?


(A) A small quantity of stover is currently sold to nuclear energy plants, but the vast majority of it is discarded as bio-waste. INCORRECT (this option does not tell us whether the investor will earn profits from the by-product.

(B) The $3.00 per bushel maximum corn price as a threshold of profitability accounts for the extra costs of separating stover from other corn byproducts and converting it to ethanol. (INCORRECT- It strengthens the argument)

(C) Only sixty percent of the potential ethanol in any given stalk of corn can be extracted using conventional techniques of ethyl hydration or yeast fermentation. (INCORRECT - Irrelevant information..The argument mentions about the method which uses stover. It mentions nothing about the what other methods do)

(D) Techniques to extract ethanol from corn that do not rely on stover require significantly more petroleum-derived energy and, as such, become less profitable when petroleum prices rise above two dollars per gallon.(INCORRECT- Strengthens the argument in a way)

(E) The quantity of stover produced annually as a byproduct of wheat farming is several times the amount that is likely to be useful in the production of ethanol. - CORRECT ( This options tells us that one of the reasons the argument cites one should invest more in wheat farms is that we obtain a by-product which MAY soon become a valuable commodity. But what if this assumption were false ?? It could happen that only a small part of the stover produced may find some use. And that the large part does not find any use..)

IMO E.

Whats the OA ?

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by cans » Mon Sep 05, 2011 5:45 am
I don't know if my answer is correct or not. But here goes my explanation:

A) It tells us about the present use of stover which is not at all related to the future use (Extraction of Ethanol). So irrelevant.

B) This is good as $3 includes everything.

C) Irrelevant. (We don't know whether new technique extracts 80% or 40%. So can't compare)

D) Actually supports. Other alternates are expensive.

E) Suppose we produce 100 units and required unit is only 1. 99 units go waste. And if someone else also invests, he will also have that 1 unit.. More Supply and less demand. Not profitable investment.

Thus E
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by Acorn » Mon Sep 05, 2011 8:17 am
E should be the answer.

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by Deepthi Subbu » Mon Sep 05, 2011 11:10 am
The OA is E

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by navami » Wed Sep 07, 2011 12:24 pm
E weakens. as it says the production of corn for ethanol generation will generate more than enough stover,
This time no looking back!!!
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by mankey » Sat Oct 01, 2011 12:07 pm
Why not A. Will appreciate if someone could explain properly?

I am stuck between A and E.

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by sl750 » Mon Oct 03, 2011 1:01 am
mankey wrote:Why not A. Will appreciate if someone could explain properly?

I am stuck between A and E.

Thanks
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The conclusion is about investing in wheat farms as a method to increase profitability, as the currently worthless stover will soon become a valuable commodity

Choice A is irrelevant as it does not help us determine why investing in wheat farms is a non- profitable idea

Choice E talks about supply demand. If the farms generate more waste than is required to produce Ethanol then investors cannot expect to make rapid growths in profit