Explanation:
to pick someone's brains. phrase. If you pick someone's brains, you ask them to help you with a problem because they know more about the subject than you.
It’s the planet can protect
It is significant because a prominent leader was suggesting that the unequal treatment of African Americans was in direct opposition to the principles of the Declaration of Independence.
Grover proves that he is a real friend to Percy. For example, during the battle between Percy and Ares, Grover supports Percy throughout the conflict.
I'm sorry I only have the answer for the first question. I hope this helped you enough though