We are very careful when We tag a question.

This passage comes from only the OG mentioned in the tag.

It is not present among the 320 questions of powerprep free software

Here we do have all the questions listed out https://gre.myprepclub.com/forum/gre-power ... -3118.html

Moreover, in this PDF https://gre.myprepclub.com/forum/vince-and ... 12946.html which is the book released by skypetutor the passage is not included.

Yet another link that confirms what we say https://www.observerbd.com/2015/09/19/111369.php


Best Regards

Except for the Q20, would anyone please explain the Q17 - Q19?. This passage is pretty tough for me

17. The primary purpose of the passage is to

(A) describe what results when a supernova triggers the creation of chains of star-forming regions

No. this is used as a premise to introduce a new theory

(B) propose a modification in the most widely accepted theory of spiral-galaxy structure

No. Because the new theory is exciting new. So, no modification

(C) compare and contrast the roles of clouds of gas and dust in two theories of spiral-galaxy structure

No contrast. In both theories, the compression clouds are part of the same theories

(D) describe a new theory of spiral-galaxy structure and contrast it with the most widely accepted theory

Correct. Blue is the contrast

A computer simulation based on this theory has reproduced the appearance of many spiral galaxies without assuming an underlying density wave, the hallmark of the most widely accepted theory of the large-scale structure of spiral galaxies.

(E) describe a new theory of spiral-galaxy structure and discuss a reason why it is inferior to the most widely accepted theory


No inferior. It is a new way of thinking about the formation of spiral galaxies

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18. The passage implies that, according to the new theory of spiral-galaxy structure, a spiral galaxy can be created by supernovas when the supernovas are

(A) producing an underlying density wave

the wave produces supernovas

(B) affected by a density wave of spiral form

the spiral is the final result

(C) distributed in a spiral pattern

we observe the supernovas in a spiral pattern. That does not mean they are in a spiral formation

(D) located in the central plane of a galaxy

they are widespread throughout

(E) located in a differentially rotating galaxy

Correct

If many such chains were created in a differentially rotating galaxy, the distribution of stars would resemble the observed distribution in a spiral galaxy.

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19. Which of the following, if true, would most discredit the new theory as described in the passage?

(A) The exact mechanism by which a star becomes a supernova is not yet completely known and may even differ for different stars.

We do know how they form

(B) Chains of star-forming regions like those postulated in the new theory have been observed in the vicinity of dense clouds of gas and dust.

The gas and dust are inside and form the stars

(C) The most massive stars formed from supernova explosions are unlikely to evolve into supernovas.

Both theories imply the formation of novas and supernovas thanks to the compression of clouds of gas and dust. Which encompass that a nova becomes a super

(D) Computer simulations of supernovas provide a poor picture of what occurs just before a supernova explosion.

No information if we do have a poor look.

(E) A density wave cannot compress clouds of gas and dust to a density high enough to create a star.

Is the contrary.

Hope this helps

Q17 says, "according to the new theory of spiral-galaxy structure," which is the second paragraph. Then why is the answer derived from the first paragraph which underlies the new theory?

The main idea embraces the whole passages even though the new theory is in the second paragraph.

Look at the big picture.

Regards

Why is the author enthusiastic and not euphoric for the new idea in the last question? Can someone provide a hypothetical example in which the case would have been considered "Euphoric"? Because to me, the "exciting" word signaled euphoria.

I got all the questions right but took like 7 mins and 11 seconds . Also didn't comprehend very well but I guess score matters at the end . :D

I think that is not a bad pace. You can always make up in SE questions.

19. Which of the following, if true, would most discredit the new theory as described in the passage?

Here, both C and E are tempting,
If supernovas are not able to form from supernova explosions then it undermines the theory I agree.
But again we see that it is said in the passage that Supernova triggered star formation from dense of clouds of gas and dust.
If a supernova (the explosion of a massive star) triggered star formation from dense clouds of gas and dust
So, why E is incorrect.

Please Sir see my explanation above if you did not see it

https://gre.myprepclub.com/forum/if-a-supe ... tml#p37851

Regards

Redoing the passage after months

4 minutes 7 seconds and 4/4 !

Great

hello expert, can you give me outline how to answer primary purpose because i stuck with this type.

download the file here https://gre.myprepclub.com/forum/how-to-sc ... 23624.html

Please put a timer on this question.

Done!