The reference of St. Augustine adds to the the credibility of Dr. King's argument about just and unjust laws mainly by

St. Augustine was really a religious scholar and theorist of Christianity. He focused on equality and reconciliation, and in the new world, his ideas are still being used.

Explanation:

Emperor makes his case clearer and improves his reputation by citing such an influential figure in the world of ideology, and proving that he held the same perspective as he's ever been.

c hydrophobia is the answer

since he could see color, and nobody else could, he didn't find it fair that everyone else in the utopia couldn't see color but him and the giver : d