OG13 Snowmaking machines problem

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OG13 Snowmaking machines problem

by amysky_0205 » Wed Dec 05, 2012 6:57 am
OG13 #RC1
Snowmaking machines work by spraying a mist that freezes immediately on contact with cold air. Because the sudden freezing kills bacteria, QuickFreeze is planning to market a wastewater purification system
that works on the same principle. The process works only when temperatures are cold, however, so municipalities using it will still need to maintain a conventional system.

Which of the following, if true, provides the strongest grounds for a prediction that municipalities will buy QuickFreeze's purification system despite the need to maintain a conventional purification system as well?

(A) Bacteria are not the only impurities that must be removed from wastewater.

(B) Many municipalities have old wastewater purification systems that need to be replaced.

(C) Conventional wastewater purification systems have not been fully successful in killing bacteria at cold temperatures.

(D) During times of warm weather, when it is not in use, QuickFreeze's purification system requires relatively little maintenance.

(E) Places where the winters are cold rarely have a problem of water shortage.

OA: C

I chose B.

A is not mentioned in the content. so we don't know if there's other things we can pure out from it.

E is clearly not relevant.

(plz correct me if i'm thinking the wrong way!)

can someone explain B, C, and D?

thank u so much!

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by ceilidh.erickson » Fri Dec 07, 2012 7:04 am
We want to support the conclusion that municipalities will adopt this purification system, even though they can only use it during cold temperatures, and will need to keep using another system, too.

Whenever we want to support a conclusion, we have to ask ourselves - are there any logical gaps in the argument that we need to fill in? We're told that the QuickFreeze system kills bacteria - that's pretty much the only information that we're given in support of this system. If the conventional system will still need to be used, the piece of information that we're missing is: do conventional systems kill bacteria? If they do, then adding QuickFreeze won't be a benefit. If they don't, though, then adding QuickFreeze will help.

(A) the premises only tell us about bacteria in relation to QuickFreeze, so we don't care about other impurities.

(B) Just because their systems need to be replaced, it doesn't necessarily follow that they'll replace them with QuickFreeze - especially when they'll need new conventional systems, too.

(C) This answers our question about conventional systems and bacteria. It tells us that QuickFreeze would add value, by killing bacteria that wouldn't otherwise be killed. CORRECT!

(D) This strengthens a teeny, tiny bit. "When it's not cold, QuickFreeze doesn't hurt" means that we don't have anything to put in the "con's" column. But it doesn't give us much in the "pro's" column, either. And it doesn't address our outstanding question about conventional systems and bacteria.

(E) Water shortage, as you say, is not relevant to water purification.

Hope this helps!
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by riyazgilani » Sat Apr 04, 2015 8:46 am
ceilidh.erickson wrote:We want to support the conclusion that municipalities will adopt this purification system, even though they can only use it during cold temperatures, and will need to keep using another system, too.

Whenever we want to support a conclusion, we have to ask ourselves - are there any logical gaps in the argument that we need to fill in? We're told that the QuickFreeze system kills bacteria - that's pretty much the only information that we're given in support of this system. If the conventional system will still need to be used, the piece of information that we're missing is: do conventional systems kill bacteria? If they do, then adding QuickFreeze won't be a benefit. If they don't, though, then adding QuickFreeze will help.

(A) the premises only tell us about bacteria in relation to QuickFreeze, so we don't care about other impurities.

(B) Just because their systems need to be replaced, it doesn't necessarily follow that they'll replace them with QuickFreeze - especially when they'll need new conventional systems, too.

(C) This answers our question about conventional systems and bacteria. It tells us that QuickFreeze would add value, by killing bacteria that wouldn't otherwise be killed. CORRECT!

(D) This strengthens a teeny, tiny bit. "When it's not cold, QuickFreeze doesn't hurt" means that we don't have anything to put in the "con's" column. But it doesn't give us much in the "pro's" column, either. And it doesn't address our outstanding question about conventional systems and bacteria.

(E) Water shortage, as you say, is not relevant to water purification.

Hope this helps!

i am little confused about option A. option A state that there could be impurities other than the Bacteria in the wastewater. now we have been given that QuickFreez kills only bacteria. so municipalities will have to keep the conventional systems also to remove other impurities.

where am i going wrong in this..?

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by DavidG@VeritasPrep » Sat Apr 04, 2015 9:30 am
We're not trying to strengthen the idea that the municipality will need to keep using the conventional system. We're told that this is the case in the argument - the new system will only work in cold weather, so they'll have to keep the old system as well. We're asked to strengthen the argument that the municipality will buy the new system, despite the fact that this system only works when it's cold. If there are other impurities aside from bacteria, that wouldn't provide any incentive to purchase a system that's designed specifically to kill bacteria, and that only works for part of the year.
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