PT5.S1.Q12 - impact craters caused

Comments

• daniel.noah.pearlberg Free Trial Member

  July 2016 70 karma

  Premise: Lots of highly skilled workers in Eastern Europe left their jobs, moved to the West.
  Conclusion: It is likely that the remaining skilled workers in Eastern Europe are in high demand in their home countries.
  
  Well, maybe, but the conclusion doesn't necessarily follow from the premise. Maybe the workers left their jobs because the jobs don't exist anymore? In which case, there's no reason to think that the remaining workers would be in high demand. That would be a good weakener, and it's what answer choice (B) tells us.
  
  (A) would strengthen rather than weaken- if they prefer to hire workers from their home countries, then it should be likely that the remaining workers are in high demand in their home countries.
  (C) is irrelevant- what the workers who left now do in the West doesn't affect whether or not the remaining workers are in high demand.
  (D) doesn't weaken- if anything, it would strengthen the argument: If they are planning on training new workers, that should imply that the remaining workers that don't need to be trained would be in high demand.
  (E) would strengthen rather than weaken- if there are many positions left unfilled, the remaining skilled workers should be in high demand.
  
  Hope that helps
  
• Seriousbird Alum Member

  July 2016 1278 karma

  Thank you SO much for the response but I think you got the wrong question..
  The question I am referring to begins with "impact craters caused by meteorites.."
• 1 Like

  daniel.noah.pearlberg Free Trial Member

  August 2016 70 karma

  Haha whoops, sorry about that! Yeah, I think this is a tough question. The conclusion is that the explanation for why we find more impact craters in geologically stable regions must be because those areas have lower rates of destructive geophysical processes. So, why would that have to be the explanation? Well, if we assume that the meteorites causing the impact craters don't actually hit the earth more in some areas than in others, then that means that we should find just as many impact craters in geologically stable regions as we do in geologically unstable regions. So if we actually find more impact craters in the geologically stable regions even though the meteorites weren't hitting those areas any more frequently, it must be because in the geologically stable regions the impact craters are left alone more often than they are in the geologically unstable regions. For example, let's say we have 2 different areas, and each one got hit with 10 meteorites, creating 10 impact craters in each of the areas. However, one of the areas gets lots of earthquakes that mess with the impact craters and so we end up finding less impact craters in the earthquake area than in the non-earthquake area. (Earthquakes are one example of a destructive geophysical process)
  So, to reiteratet: If we assume that the geologically stable regions aren't any more likely to be hit with meteorites than are the geologically unstable regions, then the explanation for why we find more impact craters in the geologically unstable regions must be because the geologically unstable regions have lower rates of destructive processes, so the impact craters are being left alone in those regions, in contrast with the geologically stable regions that have higher rates of destructive processes that then mess with the impact craters.
  That's why (D) is correct, because it tells us that the geologically stable regions aren't any more likely to be hit with meteorites than are the geologically unstable regions.
• fahim.rahman111 Member

  August 2016 44 karma

  Let me give it a shot. So the conclusion states that the reason for more craters is because there are less disruptive geological processes. Why should we believe that to be true? The answer choice you are looking for has to make it a valid conclusion, as it is a sufficient assumption question type. Let's look at the answer choices. Try to put the answer choices in front of the conclusion and see if it leads to a valid result.
  
  Answer choice A doesn't really do anything. So what if a new meteorite erases evidence of old ones, still doesn't explain why there are more craters in more geologically stable areas.
  
  B says that the rates of geological stability vary from time to time. Still doesn't make our conclusion valid.
  
  C says the rate of meteorites striking Earth has increased recently. Still has nothing to do with why there are more craters in stable areas.
  
  D says impacts have been scattered fairly evenly throughout the Earth's surface. Ah, if they were scattered evenly, and these craters were disrupted by geological processes, wouldn't that explain why there are more craters in geologically stable areas? I think this is it.
  
  E says geologically stable regions have been studied more intensely than less stable regions. It doesn't really do much for our argument, who cares if that's the case? Still doesn't explain why there are more craters in geologically stable areas.
• Seriousbird Alum Member

  August 2016 1278 karma

  @daniel.noah.pearlberg THANK YOU!!! I get it now, it makes perfect sense..I was confused about if D was true then how would the more sensitive areas be accounted for but you explain it perfectly!!
  
  @fahim.rahman111 thank you for your explanation!