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1000 CR question TESTC No 16

Expert replies
by magical cook » Thu Mar 22, 2007 4:14 pm
Hi,

The answer is B but I think D is actually weaken this argument because if they exempt local industries from pollution regulation, its number should be increased....

Could anyone please explain why D is wrong and B is correct?

Thanks!

In 1986, the city of Los Diablos had 20 days on which air pollution reached unhealthful amounts and a smog alert was put into effect. In early 1987, new air pollution control measures were enacted, but the city had smog alerts on 31 days that year and on 39 days the following year. In 1989, however, the number of smog alerts in Los Diablos dropped to sixteen. The main air pollutants in Los Diablos are ozone and carbon monoxide, and since 1986 the levels of both have been monitored by gas spectrography.

Which of the following statements, assuming that each is true, would be LEAST helpful in explaining the air pollution levels in Los Diablos between 1986 and 1989?

(A) The 1987 air pollution control measures enacted in Los Diablos were put into effect in November of 1988.
(B) In December of 1988 a new and far more accurate gas spectrometer was invented.
(C) In February of 1989, the Pollution Control Board of Los Diablos revised the scale used to determine the amount of air pollution considered unhealthful.
(D) In 1988 the mayor of Los Diablos was found to have accepted large campaign donations from local industries and to have exempted those same industries from air pollution control measures.
(E) Excess ozone and carbon monoxide require a minimum of two years to break down naturally in the atmosphere above a given area.
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Source: — Critical Reasoning |

by rajesh_ctm » Mon May 14, 2007 8:30 pm
Looks like D to me! B is a good reason that can explain the sudden difference.
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by Cybermusings » Thu May 24, 2007 5:05 am
(A) The 1987 air pollution control measures enacted in Los Diablos were put into effect in November of 1988.
(B) In December of 1988 a new and far more accurate gas spectrometer was invented.
(C) In February of 1989, the Pollution Control Board of Los Diablos revised the scale used to determine the amount of air pollution considered unhealthful.
(D) In 1988 the mayor of Los Diablos was found to have accepted large campaign donations from local industries and to have exempted those same industries from air pollution control measures.
(E) Excess ozone and carbon monoxide require a minimum of two years to break down naturally in the atmosphere above a given area.

If D were true it would mean that the leniency meted out to industries which were earlier exempted from "pollution control measures", were withdrawn after 1988. Hence such industries would have subsequently come under strict control measures and reduced their emissions of harmful gases...Thud D is a strong reason to explain the trend between 1986 and 1989

B - The fact that a more accurate spectrometer was installed, doesn't explain the huge difference in readings. Hence B is the weakest according to me
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by Princeton Review » Fri Jun 01, 2007 12:38 pm
B indicates that the readings will be more accurate, but there's no reason to expect that they would go up or down. So it doesn't help explain the change.

D indicates that the law, prior to 1988, was not being enforced. If this is combined with the assumption that the law was enforced after the Mayor is found out, it would weaken the argument.
Matt McIver

Princeton Review Instructor
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by jrbrown2 » Thu Jun 28, 2007 6:54 am
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by mankey » Thu Nov 10, 2011 10:57 am
Not sure about this one. Please help.

Thanks.
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