Yes, I totally agree with you if not for a small word you forget to mention in that phrase.



with this in the passage

Consequently, no cosmic ray traveling much beyond 100 million light-years can retain the energy observed in UHECRs.

They perfectly match.

Hope this helps

Regards

Thank you, the test organizers are so cunning. Also, what you think my level is if I make such a mistake? Thanks in advance.

Difficult to judge based on one question only. It could be a silly mistake or something related with your English skills.

Can anyone help me to understand the 2nd question, please? it seems that the answer choice B is correct. I have been thinking why C is correct and it seems ok to be the right answer but I just can't understand why B is not the correct one. Because to me, it feels like quasar and gamma rays were plausible position for the cosmic ray's source and the last line was contradictory to this explanation for the source of those cosmic rays. I just can't find my mistake.

Venomous passage

Analyzing it as the following:

X (Supernovas) are composed by \(x_1,x_2,\) ......so forth x-rays type

Supernovas in the Milky Way are the likeliest source for most of the cosmic rays reaching Earth.

However, calculations show that supernovas cannot produce ultrahigh-energy cosmic rays (UHECRs), which have energies exceeding 1018 electron volts. It would seem sensible to seek the source of these in the universe’s most conspicuous energy factories: quasars and gamma-ray bursts billions of light-years away from Earth.

However, our X does not produce a CERTAIN type of rays which can not reach our planet BECAUSE 20% of those rays are lost every 20 millions of years. In 100 million light-years they become zero, basically.

Therefore our conclusion is the following

Consequently, no cosmic ray traveling much beyond 100 million light-years can retain the energy observed in UHECRs.



In the context of the author’s argument, the last sentence performs which of the following functions?

A) It explains a criterion that was employed earlier in the argument.

No. It is a conclusion not an explanation. it is the result

B) It shows that an apparently plausible position is actually self-contradictory.

It does not contradict anything before

C) It is a conclusion drawn in the course of refuting a potential explanation.

Yes. It is. Our potential explanation is that some other source is the origin of our rays. And the last sentence concludes that the rays from supernovas can not reach or pass over 100. The explanation is the match calculation above

D) It overturns an assumption on which an opposing position depends.

Nothing here is assumed

E) It states the main conclusion that the author is seeking to establish


The author does not establish anything. We have specific facts. Basically E says that we have an assumption but we do not. D and E says the same thing

quite a tough one!
Thanks for posting it!

I think D is almost correct but is lacking "conclusion" language.

Referring to answer choice D: I think the opposing position (distant quasars and gamma-ray bursts) assumes that these photons can travel billions of Light Years. The last sentence does overturn this assumption.

But the last sentence is ALSO ("Consequently") the conclusion, therefore C is more correct.

I still find the passage and the answer choice C confusing. It says in the passage that " no cosmic ray traveling much beyond 100 million light-years can retain the energy observed in UHECRs" and in the answer choice C " The origin is most likely no more than a little over 100 million light-years away from Earth." So if the answer choice is talking about the Origin from earth, can't the origin be like 180 million light years? so it has traveled 100 million years from its origin and is still can be seen from earth when it is 80 million light years away from earth? doesn't that mean its origin can be more than 100 million light years?

Hi Carcass GreenlightTestPrep HarishKumar: I found this official question pretty tough. I got it all wrong on both occasions I tried in last 10 days. And this was after I finished all my prep. This was pretty disheatening and shook my confidence. What should be our strategy to handle such questions on the test? Thanks.

Hi

Even though I have to release my new RC guide (I faded out because I was unsatisfied but soon will be up again in full force) the formula is ALWAYS the same

1) read the passage first
2) Take a general idea and understand the main idea(very important)
3) Create your table of contents to find important detail even though the short passage NOT always the time have a clear structure from head to toes
4) pay attention to transition words (very crucial)

Let's dive into it

Supernovas in the Milky Way are the likeliest source for most of the cosmic rays reaching Earth.

Supernovas are maybe the main source of the rays that reach the earth's surface. we are sure 90% of this

However, calculations show that supernovas cannot produce ultrahigh-energy cosmic rays (UHECRs), which have energies exceeding 1018 electron volts.

However= shift in the argument. It is there that words to put you out of balance. To create a mess. To confuse you. to send you in the corner and understand nothing

Our calculations attest that supernova CANNOT produce UHECR. Now, these rays are the same of the rays mentioned in the first sentence ? or are they different ? we do not know yet


It would seem sensible to seek the source of these in the universe’s most conspicuous energy factories: quasars and gamma-ray bursts billions of light-years away from Earth.

Would be more smart to seek the source of the second kind of rays in another source such as quasars


But UHECRs tend to collide with photons of the cosmic microwave background—pervasive radiation that is a relic of the early universe.

Ok here's the deal: we said that supernovas CANNOT produce UHECRs. So they reach the earth's surface because they come from quasar. AT THE SAME time these rays from quasar clash with the microwaves of the universe. Those who are fascinated with these arguments: are also called the rumor of the universe. They are the rumor of the big bang and still, we are able to hear that immense blast that started the universe and after millions of years...here we are


The odds favor a collision every 20 million light-years, each collision costing 20 percent of the cosmic ray’s energy.

very 20 tot years we do have a collision and the rays lost 20% of their energy. An assumption could be the following: what if far more than 100 millions of light-years from the source ? well the rays that would reach us would be zero


Consequently, no cosmic ray traveling much beyond 100 million light-years can retain the energy observed in UHECRs.

My assumption above



-------------------------------------------------------------

The answers

It can be inferred that the author of the passage would agree with which of the following about the origin of UHECRs that reach Earth?

The origin is something other than supernovas in the Milky Way.

Yes. quasar

The origin is most likely something other than very distant quasars or gamma-ray bursts.

yes true. sources quasars and gamma-ray bursts billions of light-years away from Earth.

The origin is most likely no more than a little over 100 million light-years away from Earth

yes true. we do know that the source cannot be reach anything more than 100 millions light-years far away. they would be zero. see my assumption and then conclusion above


In the context of the author’s argument, the last sentence performs which of the following functions?

A) It explains a criterion that was employed earlier in the argument.

Frankly I do not know what criterion was employed. A criterion means that a sort of comparison or making concept is employed. But here we do not have any sort of possible comparison to which a criterion (plural of criteria) is a pplied.

B) It shows that an apparently plausible position is actually self-contradictory.

No position contradict itself. we have only that such rays cannot reach the earth and the source from where they come

C) It is a conclusion drawn in the course of refuting a potential explanation.

Conclusion is for sure. see the word consequently. And yes we do have a possible (notice possible) explanation: the rays come from quasars and not supernova AND the distance is a crucial element to consider

D) It overturns an assumption on which an opposing position depends.

Convoluted wording to say: I agree with something. back to the balance. nothing of all that


E) It states the main conclusion that the author is seeking to establish

It is not the main conclusion. It is just a conclusion for a phenomenon explained

The question above is quiteeee tricky. when you deal with such questions , do the following

1) slow down and pay attention to EVERY single word in the answer choices
2) Use your table of content if you did
3) do not get confused. slow down. no rush, you have time during the test

After all if you reflect one second: the passage , basically, talked about an explanation why the rays come from this or not that. AN EXPLANATION.

All the answer choices but C says this.


Hope this hleps

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