I submit that impact of solid bodies is the most fundamental of all in

It seems like author is presenting a scientific paper about his views on a theory. The first para gives a theory

Second para says why no proof exist and further where proof can be found.

Third para explains why it are the advantages of studying the current examples to get idea about the old stuff.

1) D is the only one that covers the scope of all the 3 paragraph. Secondly, observe the author never argues for proving his point. The tone is not arguing.

2) As the process is self-erasing, to a certain extent, the earliest record would have been lost even if processes of melting and internal evolution of the planets had not occurred.

That means these processes were responsible for lost records. Evolution of planets means change in the planet.

3) If impact and accretion were not still occurring, it would be hard to come to grips with a number of difficult problems of planetary origin and early evolution

What author means is we can observe the current phenomena to understand the past phenomena. It is kind of extrapolating from the present data.



Thank you = Kudos

Hey Sreyoshi,

If impact and accretion were not still occurring---> we are concerned by accretion and not RATE of accretion.

Hope this helps.

Thank you = Kudos

+1 kudos to all the posts containing proper explanations for all questions
_________________

Hey csaluja

Notice this in the paragraph :As the process is self-erasing---> it means the process was self erasing ( such as melting of ice and evolution of plants). B says the opposite.

Hope this helps.

Thank you = Kudos

Hi,

But even if the process is self-erasing, whatever the outcome comes out and if that is not self-erasing, can we still not predict why the earliest record were lost? Option C makes sense but I am still confused regarding option B.

Hi ,
Can anyone help me with Q2.
For what i understand is why there is lack of geographical record?
lack of geographical record is due to process that is self erasing.
Even if processes of melting and internal evolution of the planets had not occurred, there is still lack of geographical record.
So from my point of view , both A and C should be wrong. Can someone help me with this?

guptakashish02

Correct. The question asks for the reasons for the lack of a geological record.



Self-erasing is the reason to a certain extent. it is not the sole reason. Observer the following line from the passage.

As the process is self-erasing, to a certain extent



The remaining extent for the loss of the geographical records is the "processes of melting and internal evolution of the planets". Option C correctly conveys this meaning by saying "a process of change in the planets themselves".

Hence option C is correct.
_________________

In Question 1: Meaning of underscore is important to answer the question correctly.

Underscore - To emphasize the importance

Official Explanation for Q1

Answer: (D)

The purpose of the passage is to discuss the importance, for those wanting to learn more about the evolution of our planets, of the “impact of small bodies.” The passage specifically advocates using current processes to understand the historic processes.

(A) is wrong because there is no “common misconception” mentioned.

(B) is incorrect because accretion plays an important role

(C) is tempting because the passage does mention this. But the primary purpose is not only to discuss the importance of extrapolation but to assert the importance of the “impact of solid bodies” on the formation of our solar system.

(E) There is no talk in the passage about scientists potentially missing out on an opportunity.

Official Explanation for Q3

Answer: (A)

The sentence, “This is fortunate…” describes how scientists can observe current events taking place in or regarding planets to learn more about “difficult problems of planetary origin…”.

(A) supports this idea best. ‘Extrapolating’ means taking information from one instance and applying it to an unknown instance (in this case, the early evolution of planets).

(C) is a tempting answer. But scientists are relying on a host of planetary occurrences (“the dynamics of their orbital evolution, and the effect...”). While accretion is mentioned as an important process currently taking place, it doesn’t explicitly say the rate of accretion is key to understanding “a number of difficult problems.”

Official Explanation for Q2

Answer: (C)

The passage mentions that “the geological record…has been lost.” In the following sentence, it mentions that “melting and internal evolution” can erase the early geological history of a planet. Therefore, we can infer that a process within the planet themselves can erase the geological record. Answer: (C).

(A) is incorrect because nowhere does it mention the violence of any initial impact.

(B) is the opposite of what we are looking for. The processes that do not leave any record of the geological history are self-erasing.

(D) is incorrect since the passage does not talk about this hypothetical collision.

While accretion is still occurring, it does not account for why there is no geological record of the history of planet. Thus (E) is wrong.

Hi everyone,
Took 7:50 minutes and got 2/3 correct.

P1: importance of solar bodies' impacts
P2: absence of records and importance of last phase
P3: why last phase is important

MP: discuss the importance of the impact of solar bodies and the methodology used for studying it

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

1. The primary purpose of the passage is to

Pre-thinking:
Refer to main point to analyze the answer choices


A. present evidence that argues against a common misconception in the formation of planets
No common misconception. Hence incorrect

B. undermine a claim regarding the role accretion plays in planetary evolution
No claim is undermined. Hence incorrect

C. argue for the importance of using existing planetary conditions to understand prior cosmic occurrences
Patrtial scope related only to 3rd paragraph. Hence incorrect

D. underscore the importance of an astronomical process and describe ways in which we can understand this process
Correct since the astronomical process is the impact of SO and the last paragraph shows how to understand it. Hence correct

E. discuss how, unless immediate action is taken, astronomers will squander an opportunity to better understand planetary formation
Never mentioned. Hence incorrect

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

2. It can be most reasonably inferred that which of the following accounts for the lack of a geological record concerning the history of impacts on the planets?

Pre-thinking:
The lack of geological record is linked with events that are self erasing.

A. the violence of the initial impact
The violence is not cited. Hence incorrect

B. an outcome that is not self-erasing
Opposite. Hence incorrect

C. a process of change in planets themselves
Not perfectly in line with pre-thinking but if an event is self erasing we can infer that there will be a change in the planets. Hence correct

D. the absence of proof relating to a hypothetical collision
There are proofs but we cannot study the event itself. Hence incorrect

E. the ongoing process of accretion
This process if any helps us study the impact. Hence incorrect

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

3. The author suggests that at least some of “a number of difficult problems...”can be understood by

Pre-thinking:
because impact and accretion are still occuring

A. extrapolating from observable phenomenon
Correct. we can study impact and accretion which are phenomenon still occurring. Hence correct

B. anticipating the result of the collision of small bodies
Never mentioned. Hence incorrect

C. studying the rate of accretion on planets
The rate is never mentioned. Hence incorrect

D. observing the internal process of planets
investigation of nature of small object is mentioned. not planets. Hence incorrect

E. discounting the dynamics of how orbits change over time
Not related to answer " a number of difficult problems". Hence incorrect

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

It is a good day to be alive, cheers!

Could you please explain what does "extarpolation" mean in the last question? Thanks
_________________

"Extrapolation" means generalization basis current or past data. In this context, the author is highlighting the lack of evidence to study this phenomenon, which is quite crucial for planetary creation, in detail. However, the author says this can be done by generalizing the ongoing phenomenon of accretion and impact to unknown scenarios (possibly "past" scenarios of planetary creation for which we are still seeking answers)

IMHO the answer choice has been chosen where the author's meaning gets distorted and fragments of sentences have been conveniently picked up to choose the answer.

2. It can be most reasonably inferred that which of the following accounts for the lack of a geological record concerning the history of impacts on the planets?

A. the violence of the initial impact - no violence is discussed
B. an outcome that is not self-erasing - incorrect, it is self erasing
C. a process of change in planets themselves - honestly this is nowhere suggested in the passage
D. the absence of proof relating to a hypothetical collision - not relevant
E. the ongoing process of accretion - this should be the answer. Read the below line

"Simply put, the collision of smaller objects is the process by which the terrestrial planets were born. On the surface, that the geological record of the earliest history of impacts on the terrestrial planets has been lost, is troubling. As the process is self-erasing, to a certain extent, the earliest record would have been lost even if processes of melting and internal evolution of the planets had not occurred.

The question is asking about the process (bold) that caused these geological erosion. The process is accretion itself. Moreover, it clearly states (underlined) that even if we discount the planets internal processes such as melting, internal evolution etc we would still not find any evidence since the accretion process is self erasing.

I welcome any thoughts.

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________