Ethanol, a fuel derived from corn, can be used alone to power cars

Question

Ethanol, a fuel derived from corn, can be used alone to power cars or along with gasoline to reduce the amount of gas consumed. Unlike gasoline, ethanol is easily renewable since it is primarily converted from the sun's energy. Moreover, compared with conventional gasoline, pure ethanol is a cleaner-burning fuel. To save energy and reduce pollution, many individuals advocate the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.

In evaluating the recommendation to increase the use of ethanol, it would be important to research all of the following EXCEPT:

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline
(C) Whether ethanol is as efficient a fuel as gasoline
(D) Whether it is possible to produce more ethanol than is currently produced
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline

VarunBhardwaj · Accepted Answer

The main idea is to   save energy and reduce pollution  .And we need to evaluate if the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced. 
 Incorrect.The idea is to save energy.So, We need to evaluate the energy IN and energy out. 
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline.
 Correct.This statement is the repetition of the argument itself. 
(C) Whether ethanol is as efficient a fuel as gasoline
 Incorrect.It is mentioned that Ethanol is a cleaner fuel. 
 Lets Assume , Ethanol produce 50 % less pollution than gasoline.
But if it is only 10 % as efficient as gasoline, so the amount of ethanol burnt will be 10 times more than gasoline and it will produce more pollution in total.
In order to evaluate the argument , we need to know the efficiency  
(D) Whether it is possible to produce more ethanol than is currently produced
 Incorrect. Since, Argument advocates the  increased usage  of ethanol.We need to see if the production can be increased to meet the demands. 
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline
 Incorrect.The idea is to reduce pollution.So, We need to evaluate the pollution produced by both the fuels.

sun01 · Answer

Let me explain.
This argument is about recommendation of increased use of ethanol with/without gasoline.

The choices are

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.   Yes to research  
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline-  No to research. because argument already says that  Ethanol, a fuel derived from corn, can be used alone to power cars or along with gasoline to reduce the amount of gas consumed. . 
 
(C) Whether ethanol is as efficient a fuel as gasoline.-   Yes to research  
(D) Whether it is possible to produce more ethanol than is currently produced.-   Yes to research  
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline - Yes to research

shasara · Answer

I'm unable to improve by verbal and quantitative scores

gmat2014p · Answer

Hello there, 
Can some one please explain why D is wrong? I do not think increased usage of ethanol necessarily translates into measuring production of ethanol. Even with current production level there can be increased usage. 
ex. 
today 100 litres of ethanol is produced but only 10 litre is used as fuel 
In future still 100 litres may be produced, but 20 litres may be used as fuel

prasi55 · Answer

The recommendation is to increase the usage of ethanol. But what if the current technology does not allow it?
Your example does not tackle the corner case. What if the ethanol currently produced is woefully inadequate to meet the demand? In this case, the technology (or the ability to produce more ethanol) becomes the bottleneck.
Your example would be useful in evaluating a recommendation to optimize the use of the ethanol already being produced.

ssriva2 · Answer

In evaluating the recommendation to increase the use of ethanol, it would be important to research all of the following EXCEPT:

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline
(C) Whether ethanol is as efficient a fuel as gasoline
(D) Whether it is possible to produce more ethanol than is currently produced
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline

B is repetition of premise and thus the best answer.

shubham2312 · Answer

not able to understand why B is answer

my take is A
reason for that is 
in case if we need more energy to produce the corn than ultimately produced energy than it wont be a great idea to use this method 
kindly someone explain it

shubham2312 · Answer

thanks a lot 
actually few minutes after posting someone got my attention to the word except 
thanks a lot once again

rezaulnsu · Answer

It is an Evaluate X question. So, needs testing with both yes and no.
Try yes..the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced. if so, weaken the conclusion, since it will be wasteful.
Try No..the energy required to grow and process the corn used as fuel is not greater than the amount of energy ultimately produced. if so, using ethanol would be efficient. So, strengthened.
So, A is not correct option, since it passed two way test or variance test.
Option Bis correct option since it fails the test.
The structure is..whether...or..So, if applied, 
One extreme:more energy is saved when using ethanol in conjunction with gasoline. Conclusion holds and strengthens.
Opposite extreme:more energy is saved when using ethanol in place of gasoline. Still, strengthenn. So cleary fails the test.
Option D :
if yes, it is possible to produce.......strengthens
if no, it is not possible to produce....weaken because if so, how can it can be recommended to increase usuage of ethanol? Increased usuage needs more production. Before, more production is not needed, but now it is needed to increase production because of increased demand dueto increased recommened usage.
TY.

b9n920 · Answer

Ethanol, a fuel derived from corn, can be used alone to power cars or along with gasoline to reduce the amount of gas consumed. Unlike gasoline, ethanol is easily renewable since it is primarily converted from the sun's energy. Moreover, compared with conventional gasoline, pure ethanol is a cleaner-burning fuel. To save energy and reduce pollution, many individuals advocate the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.

In evaluating the recommendation to increase the use of ethanol, it would be important to research all of the following EXCEPT:

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline
(C) Whether ethanol is as efficient a fuel as gasoline
(D) Whether it is possible to produce more ethanol than is currently produced
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline

Hi all,

I think nobody has posted a strong reason why choice D is necessary.  Is it possible to produce more ethanol than is currently produced?  Why this question is important? I think, the answer lies in the line:  Unlike gasoline, ethanol is easily renewable since it is primarily converted from the sun's energy.  We need to replenish the current production of corn every now and then when there is more demand of energy. This is included in the advantages of Ethanol as a fuel.

Thanks.

chaudhurysr · Answer

I still am not very clear why B is the correct answer, although I see that other options are clearly incorrect.

Answer B can be interpreted in another fashion as well: 
Whether   more   energy is saved when........ blah blah  
a) If Yes, then Ethanol use is recommended. 
b) If No, that means less energy is saved using Ethanol (either alone, or in conjunction) as compared to Gasoline. In that case, Ethanol is not recommended.

So we do get "two paths" here, and hence option B is also important for research!!

AdityaHongunti · Answer

Ethanol, a fuel derived from corn, can be used alone to power cars or along with gasoline to reduce the amount of gas consumed. Unlike gasoline, ethanol is easily renewable since it is primarily converted from the sun's energy. Moreover, compared with conventional gasoline, pure ethanol is a cleaner-burning fuel. To save energy and reduce pollution, many individuals advocate the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.
understand :
1) E - derived from corn - can be used in place of OR with G
2)E- renewable
3) E- CLEANER burning (note the comparison, The author does not say that E is Clean . It is relatively clean)

Goal- SAVE energy and REDUCE pollution
Plan - INCREASE USAGE OF E as a PRIMARY (major source) of fuel with or in place of a G

Question : Evaluate EXCEPT : 4 options will presnt relevant info ie asking them yes no or knowing the answr to those question will IMPACT CONCLUSION

Author's reasoning : Author thinks that because of some advantages E has over G , He recommends using E. why? because it is CLEANER and RENEWABLE . but are these advantages ENOUGH TO ENSURE THAT E CAN BE USED AS A PRIMARY SOURCE?

Answer choices :

(A) Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.
: Directly IMAPCTS THE GOAL : SAVING ENERGY
(B) Whether more energy is saved when using ethanol in conjunction with or in place of gasoline
: the question asks if E will save MORE energy when used IN CONJUCTUON WITH G or will MORE energy be used when used IN PLACE of G. this comaparison is irrelevenat. As author already states that whichever (with or without G)is already an option. so knowing which will save more is irrelevant. AS LONG AS ENERGY IS SAVED EITHER WAY.
(C) Whether ethanol is as efficient a fuel as gasoline
: if E is less efficient than G , then the final TOTAL amount of E would be same and thus will have no advantage.
(D) Whether it is possible to produce more ethanol than is currently produced
: Conclusion states that E be used AS A PRIMARY SOURCE. To be a primary source ,E has to bear a huge demand . But what if there is no enough supply?
(E) Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline 
: Goal : REDUCE POLLUTION . Directly IMAPCTS

Sarjaria84 · Answer

Hi Experts  AjiteshArun   VeritasKarishma   DmitryFarber

I too have the above doubt. I am not really sure why is the option 'B' being interpreted as below (from Manhattan RC book)

"The conclusion makes no distinction between these two methods of using ethanol; it just recommends in general that we do use ethanol. If more energy is
saved using ethanol in conjunction with gasoline, then the conclusion holds. If more energy is saved using ethanol in place of gasoline, then the
conclusion holds. Either way, it's the same thing."

What I understand from the 'Yes'/ 'No' test that the entire statement is tested for YES and No. It should be as below as per me,

Yes, more energy is saved when using ethanol in conjunction with or in place of gasoline.

No, more energy is not saved when using ethanol in conjunction with or in place of gasoline.

The above gives two paths as well but is the option 'B' incorrect because it is the rewording of the conclusion and in Evaluate Type questions we attack or test using YES/NO method the underlying assumption/s and not the conclusion itself?

Thanks
Saurabh

AjiteshArun · Answer

Hi  Sarjaria84 ,

I agree that option B could be made a little clearer. The author(s) intended that option to be interpreted as follows:

1.  We should do either X or Y.  where X is ethanol + gasoline ( in conjunction with ) and Y is ethanol alone ( in place of )
2. We can't tell whether that recommendation is good by checking whether X is better than Y or Y is better than X.

Your interpretation leads to a slightly awkward reference to "more energy" (more energy than what?), which is why I don't feel that B is wrong. It'd be great to get more responses on this though.

JonShukhrat · Answer

Dear  AnthonyRitz

Could you please check my reasoning? I had difficulty eliminating answer choices A and E.

The stimulus juxtaposes ethanol with conventional gasoline. The purpose from increased usage of the former is “to save energy and reduce pollution”. So, we need to clarify which choice is useful to determine whether we save energy and reduce pollution with ethanol.

A)  Whether the energy required to grow and process the corn used as fuel is greater than the amount of energy ultimately produced.

I don’t like this choice because it doesn’t help compare ethanol with gasoline. Even if the answer to choice A were “yes”, we would simply know that more energy is spent to produce ethanol than the amount it gives. But this could be true for gasoline either. I know that 118 J of energy in crude oil is used to produce 100 J of energy in the form of gasoline. If, say, 110 J of energy were spent to produce 100 J of energy in ethanol, then using ethanol still saves energy.

If the answer were “no”, we still wouldn’t be able to evaluate the argument.

E)  Whether the process of growing corn for fuel would result in as much pollution as does the production of conventional gasoline.

I don't like this choice for the same reason. If the answer is “yes”, then we know that growing corn results in  as much pollution as  (not more than) does the production of gasoline. Even if growing corn produces as much as pollution, ethanol can still be advisable because we have already been told that ethanol is a clearer-burning fuel.

And we don’t know whether processing the corn produces any pollution. We know that “it is primarily converted from the sun's energy, not from burning coal or any other conventional energy source”. Hence, responding either “yes” or “no” may give the same result.

I hope I was able to articulate my doubt. Many thanks beforehand.

AnthonyRitz · Answer

Jon,

I don't share these concerns. To me, A and E are both definitely relevant. Let me see if I can address your doubts:

First of all, regarding A, if an energy source costs more energy than it produces, then it cannot be a viable way to "save energy" by the very definition of the phrase. Now, if you want to get into physics and the Second Law of Thermodynamics, I suppose you could argue that  everything  costs more energy than it produces, but that cannot possibly be the intent here, so I'm going to ignore that and assume that it costs "us" more energy to produce (not counting, say, the sun's energy put into the corn growth, etc.) than we can obtain from it. In that case, again, there is no way that ethanol is usable to achieve at least one of our purposes. Furthermore, though it doesn't really matter, we simply have to understand that gasoline does not (in this same sense) cost more energy than it produces -- otherwise we would not be using gasoline as fuel, almost by definition. You're being far too rigid, I'm afraid, demanding an explicit comparison in every answer choice. Answer A is relevant as a big  part  of the story even if we knew nothing about gasoline, but really we know quite a lot about gasoline if we dig a bit.

As for E, we now have a comparison. Of course it doesn't make  every possible  comparison, but if our goal is to "save energy and reduce pollution" (note the "and"), then something that does not reduce pollution certainly cannot achieve this goal, whether or not it produces more energy. Now, you noted the "cleaner-burning" fuel bit, and that's true and inarguable, but if ethanol, while cleaner to burn, is dirtier to produce, then at the very least we have new, real doubts about whether ethanol can, in net, "reduce pollution." You're not going to get certainty on these, so you have to give up on that. To weaken, it's enough to create genuine doubt where doubt did not exist before.

Meanwhile, the correct answer B is just wildly irrelevant. It does not matter in any way, shape, or form. Instead of gasoline or in conjunction with it? Who cares? We've already said that either is fine.

ellerstak · Answer

The answer is (B) "Whether more energy is saved when using ethanol in conjunction with or in place of gasoline", simply because this answer modifies the conclusion. The conclusion is arguing to increase usage of ethanol "in conjunction with or in place of gas" in order to save energy and reduce pollution. (B) evaluates whether "in conjunction" or "in place of" is better. We don't care about this. The claim just wants to save energy/reduce pollution by any means possible.

Conclusion: To save energy and reduce pollution, many individuals advocate the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.

Conclusion: To save energy and reduce pollution, many individuals advocate the increased usage of ethanol as a primary fuel source in conjunction with or in place of gasoline.

AnirudhaS · Answer

(C) Whether ethanol is as efficient a fuel as gasoline

I don't understand why C cannot be the answer.
Why would we want to research if its more efficient or not.
We know that ethanol is cleaner than gasoline and can be easily produced.
So even if its not as efficient, since its better for the environment we need to use it.

MartyTargetTestPrep · Answer

Hi AnirudhaS.

Notice that, if ethanol is less efficient than gasoline, then we may have to burn much more ethanol than gasoline to generate the same amount of energy.

If so, it may be that, even though ethanol burns cleaner than gasoline, we would have have to burn so much more ethanol than gasoline that we would end up generating more pollution by using ethanol than we'd generate by using gasoline.

So,  (C) whether ethanol is as efficient a fuel as gasoline  is something that would be important to research.

Ethanol, a fuel derived from corn, can be used alone to power cars

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Ethanol, a fuel derived from corn, can be used alone to power cars

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