somtsat99 wrote:
Can Anyone explain the answers to question 2 and 4 in detail. Also what could be the level of this official RC ? I find it very hard. Got only 2 answers correct.
Btw, hi
ashygoyal, I can read Q2 only, so I will post its explanation. But I will not type as exact as what's written in
OG, because I believe that the following (in my own words) will better help test takers understand how to understand the question and how to drive to the correct answer.
My 2 cents on Q2.
The discovery of which of the following would call into question the conclusion mentioned in line 16?According to the passage, the conclusion is
"that asteroids larger than 200 meters across are multicomponent structures or rubble piles".
--> We're talking about "asteroids larger than 200 meters across", so eliminate (A) and (B) as these options mention asteroids smaller than 200 meters in diameter.
A. An asteroid 100 meters in diameter rotating at a rate of once per week
B. An asteroid 150 meters in diameter rotating at a rate of 20 times per hour[/color]
In order to weaken the above conclusion, we need to prove that asteroids larger than 200 meters across are NOT multicomponent structures or rubble piles.
Now, let's ask "what evidence does the author use to reach the conclusion??" --> The author argues earlier in the 1st paragraph that
"If asteroids are rubble piles, however, the tail representing the very fast rotators would be missing, because any loose aggregate spinning faster than once every few hours (depending on the asteroid’s bulk density) would fly apart."
. In other words, rubble piles don't rotate faster than once every few hours, because if they do, they would fly apart.
It seems to be quite clear now, right? In order claim that asteroids larger than 200 meters across are NOT multicomponent structures or rubble piles, we just need to prove that these asteroids rotate faster than once every few hours, a character that is totally contrary to that of rubble piles!
[color=#ec008c]C. An asteroid 250 meters in diameter rotating at a rate of once per week
--> Still slower than "once every few hours". OUT
D. An asteroid 500 meters in diameter rotating at a rate of once per hour--> Yes, that's it! "a rate of once per hour" demonstrates that the asteroid rotates faster than once every few hours. CORRECT!
E. An asteroid 1,000 meters in diameter rotating at a rate of once every 24 hours--> Still slower than "once every few hours". OUT
Hope this helps!