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Gaurav 2013-fall Master | Next Rank: 500 Posts
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Post Thu Mar 01, 2012 10:16 pm
IMO C. More the distance traveled by the light to reach the theodolites, more the refraction error.
see lines 33-38.

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dipti.oec Junior | Next Rank: 30 Posts Default Avatar
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Post Thu May 02, 2013 8:45 pm
Answer is C.

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ahe207 Newbie | Next Rank: 10 Posts Default Avatar
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Post Tue Feb 12, 2013 10:20 am
@vongochao

I think anybody who picks C has chosen the "smart" answer, but unfortunately it's not the "correct" answer since you'd have to make the jump from "humid" to "different temperature (and pressure)", which is just too much of a jump for a GMAT question since it's not in the text.

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dipti.oec Junior | Next Rank: 30 Posts Default Avatar
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Post Thu May 02, 2013 8:45 pm
Answer is C.

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ahe207 Newbie | Next Rank: 10 Posts Default Avatar
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Post Tue Feb 12, 2013 10:20 am
@vongochao

I think anybody who picks C has chosen the "smart" answer, but unfortunately it's not the "correct" answer since you'd have to make the jump from "humid" to "different temperature (and pressure)", which is just too much of a jump for a GMAT question since it's not in the text.

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HA PHUONG Junior | Next Rank: 30 Posts Default Avatar
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Post Sun Jun 04, 2017 3:00 am
C

Line 30: Because light traveling down from a summit passes through
many such layers, a surveyor could
sight a mirage rather than the peak
itself.

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vinitkhicha Junior | Next Rank: 30 Posts Default Avatar
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Post Tue Oct 14, 2014 2:11 am
IMO Option C is the best one as the passage specifically mentions that refraction error occurs due to the air reaching the theodolites passing through many different air layers. The option B is not appropriate because it only mentions humid air and not many diff air layers which vary in temperature and pressure.

PS:
Quote:
DanaJ and Administrators , Why do we get only one sample question from the passage and not the whole question set. It should be made mandatory while posting RCs to post the whole question set with it, isn't so??

_________________
Great dreams of great dreamers are always transcended- APJ

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Phoenix22 Newbie | Next Rank: 10 Posts Default Avatar
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Post Sat Aug 10, 2013 8:21 am
Answer is A.

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tavelano Newbie | Next Rank: 10 Posts Default Avatar
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Post Mon May 20, 2013 7:41 am
Answer: C

We can solve this problem but using logic and confirm using context clues.

B and D end being wrong because humid air or low pressure air does not translate to CHANGING temp/pressure i.e. it could all be the same still. The 2nd problem is that even IF that did mean changing temp/pressure it does not mean that it affects measurements since we could still be measuring at very close distances

The conditions in C allow the most probability to cause errors since, from the passage, we know that greater the measuring distance the more refraction errors because there is more distance and thus more changes in air/pressure. Also, we can feel comfortable because the major fix to refraction errors was to carry in 5-12 miles from the summit

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vongochao Junior | Next Rank: 30 Posts Default Avatar
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Post Tue Feb 12, 2013 9:16 am
B.
everbody! humid air that means it's containing water, whenever light go through water with different temperature will have a refraction.

otherchoices are the ways how to correct errors

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rajeshsinghgmat Master | Next Rank: 500 Posts Default Avatar
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Post Thu Feb 07, 2013 6:50 pm
C the answer

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ahe207 Newbie | Next Rank: 10 Posts Default Avatar
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Post Sat Jul 28, 2012 12:51 pm
I understand (and don't necessarily disagree) why people are saying C, but humid air has both a different temperature and pressure than non-humid air.

If we are able to bridge that gap (from humid to "different temperature and pressure), than why isn't B correct?

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yaddict Newbie | Next Rank: 10 Posts Default Avatar
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Post Tue Jul 17, 2012 11:42 pm
I vouch for C, as mentioned in the passage refraction would create error in cases where we have differences in temperature and pressure; thus we need to look at choice that implies such variations.

A. When there are local variations in sea level : Sea level unevenness leads to another type error thus unrelated. (line 53)
B. When light passes through humid air : humidity is out of scope, was never discussed
C. When theodolites are used relatively far
from the mountain peak. : seems a plausible option as it may signify large variation in T and P with altitude (line 30-35
)
D. When weather balloons indicate low air temperature (T) and pressure(P). : Its changes in T and P not their absolute value that results in error
E. When sea level has been carried in to within five to twelve miles of the summit.: irrelevant to the question

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angel510 Newbie | Next Rank: 10 Posts
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Post Fri Jun 08, 2012 10:39 pm
I agree with C as it seems to be the most obvious answer
Where is this question from? Please post the OA

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minhchau1986 Junior | Next Rank: 30 Posts Default Avatar
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Post Fri Apr 27, 2012 7:53 am
Tough one.
A is out of scope. Local variation is not the cause of refraction' error
B Tricky. Light passed through the air with different temperature and pressure. Does not specifically mention humid. Eliminated
C hold on
D launch balling to measure the Temperature and pressure change to reduce the refraction error. It means they can measure when it is low temperature and pressure.eliminated.
E out of scope.
If it is far relatively far for the peak, it increases the chance of refraction' error. Answer is C

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