PT149 S4 Q6 ExplanationAstrophysicist: Gamma ray bursts

Answer choices, explained

1. A

   Weakens5% picked this

   No other GRBs with unusual properties have

   This was one of our objections -- "what if this is a total outlier? Let's not ditch a system because of one stray data point".

   5%
2. B

   Too Weak10% picked this

   The classification of GRBs can sometimes be made on the basis

   Answer choices with the strength of "can, may, might, some, sometimes" are almost always wrong on Strengthen, Weaken, and Paradox, because they have such little impact. If anything, this answer would probably weaken, because it sounds like we could just go ahead an call this unusual GRB a "long" one (classify it on duration alone, and don't worry about how all its other properties matched up with short GRBs).

   10%
3. C

   Correct76% picked this

   Properties other than duration are more important than duration in the proper classification of

   Why this is right

   This helps us to complete the sentence, "We should get rid of this labeling system, because ..." Because according to this labeling system we would classify this as "long" (it had a long explosion duration), but according to this answer choice, the other properties, the ones that correspond more with "short" are more important. So this answer, combined with our facts, makes it seem like our current labeling system would slap the wrong label on this recent unusual GRB.

   Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.

   76%
4. D

   Weakens, if Anything3% picked this

   GRBs cannot be classified according to the different types of cosmic events

   By denying the possibility of an alternative classification system, we're certainly not helping this argument. If anything, it's making it seem more like we'd be stuck with our current labeling system.

   3%
5. E

   Unclear Impact5% picked this

   Descriptive labels are easily replaced with nondescriptive labels such as "type I"

   This answer seems somewhat tempting, because it makes it seem like we could easily change our labeling system. But it's dodging the real issue of how we would categorize this weird GRB we just sighted. Changing the names from "long" and "short" to "type 1" and "type 2" wouldn't really solve the classification problem with this GRB. Would we call it a type 1 or 2? It has the duration of a typical type 1 but all the other properties match type 2. This is not really solving the problem, just re-naming the same problem. Also, the Conclusion isn't actually saying "we should get rid of these labels and create new ones to replace them". It's only saying "we should get rid of these labels". It may be that the author just thinks we should stop grouping them all as "short" / "long" but not be proposing that we come up with a different classification system to replace them. When it comes to the main issue of, "should we stop labeling them short/long?", (C) makes a stronger case for why these old labels are bad. Saying "they could be easily replaced" doesn't make a strong case for the idea that the old labels are bad.

   5%