What is the main idea of this excerpt? A. Some students never get a real chance to succeed, but they need
to avoid causing problems for those who do.
B. Family must always be a person's first priority, but making an
honest effort in school is important, too.
C. Adults should always give their children the support they need to
succeed in school and in life.
D. Even those who struggle in their lives outside of school have a
responsibility to make an effort with their education.

D. Even those who struggle in their lives outside of school have a  responsibility to make an effort with their education.

Explanation:

In the given passage, President Obama reiterates the importance of education irrespective of one's personal life. This Back to School speech stresses the need for kids to focus on their academic life no matter what circumstances they face in life.

By stating that "none [of the circumstances of your life] is an excuse for neglecting your homework or having a bad attitude in school", the President advised the students/listeners that it is important to try to make school work. Thus, the main idea of the excerpt is that everyone has the responsibility to make an effort with their education.

In this chapter from the novel, the maid is giving her account of the murder of a man. She is telling how the old man asked a young man for directions, who answered with a violent murder. The shock of the whole chapter is that there are so many details regarding the murder committed by Mr. Hyde, but no apparent signs as to why he did it. Therefore, your best answer is why Mr. Hyde killed the man.