Why is the answer e?? I thought the best was a. I don't understand why sulfur 33 is rarely found. I thought what they had found were HIGHER THAN NORMAL concentration. Meaning today's diamond could still have s33 but less of it. Halp.
AHH an MSS question. Those always get me. Lets figure this beech out.
Scientist examined diamonds that were formed on Earth about 2.9 billion years ago. These diamonds had a higher-than-normal concentration of sulfur-33. This concentration can be explained only by certain chemical reactions that are stimulated by ultraviolet light. If there had been more than a trace of oxygen in Earth's atmosphere 2.9 billion years ago, then not enough ultraviolet light would have reached Earth's surface to stimulate in chemical reactions.
So: If higher-than-normal S33 ---> chemical reaction UV If more than a trace of oxygen --> ~chemical reaction UV From this we can infer that if more an a trace of oxygen is present, the there cannot be a higher than normal S33. Therefore: the correct answer should be somewhere along the lines of that there isn't more than a trace of oxygen in Earth's atmosphere 2.9 billion years ago.
A) is not correct. We don't care about "most diamonds", we only care about "these diamonds" that are relevant to the stimulus. Restates premise 1 C) Feels like the correct answer to me D) Out of scope? I mean the stimulus gives us nothing about what happens before or after 2.9 billion years E) Feels like one of those DAFAQ answer choices. I mean...WHAT?
I actually went back to the answer key and checked this question. The answer is in fact C, not E. Phew, I haven't lost my mind.
Comments
Scientist examined diamonds that were formed on Earth about 2.9 billion years ago. These diamonds had a higher-than-normal concentration of sulfur-33. This concentration can be explained only by certain chemical reactions that are stimulated by ultraviolet light. If there had been more than a trace of oxygen in Earth's atmosphere 2.9 billion years ago, then not enough ultraviolet light would have reached Earth's surface to stimulate in chemical reactions.
So:
If higher-than-normal S33 ---> chemical reaction UV
If more than a trace of oxygen --> ~chemical reaction UV
From this we can infer that if more an a trace of oxygen is present, the there cannot be a higher than normal S33.
Therefore: the correct answer should be somewhere along the lines of that there isn't more than a trace of oxygen in Earth's atmosphere 2.9 billion years ago.
A) is not correct. We don't care about "most diamonds", we only care about "these diamonds" that are relevant to the stimulus.
Restates premise 1
C) Feels like the correct answer to me
D) Out of scope? I mean the stimulus gives us nothing about what happens before or after 2.9 billion years
E) Feels like one of those DAFAQ answer choices. I mean...WHAT?
I actually went back to the answer key and checked this question. The answer is in fact C, not E. Phew, I haven't lost my mind.