Who are martin luther kings audience with letter from birmingham jail?

Which of the following is an example of the pull factor known as economic migration? a. better educational opportunities pulling people towards a new country b. mexican laborers entering the us to work in agricultural jobs c. joining family members that are already in a new country d. crop failures driving people away from their country i am unsure on this question, i was thinking b? but i could be wrong.

Over time, who did the nature of slavery change in america

In this diary only in researching sidney montz or can it be used to research broader subjects