How did each interpret the concept of American freedom? What contributions did they make to their times?

The directions my professor gave me are, “I DO NOT want three separate biographies but a paper that compares and contrasts the individual selections in a flowing narrative that focuses on the idea of freedom. How did each interpret the concept of American freedom? What contributions did they make to their times? What challenges did they face? How did they see the idea of freedom extended to others?”chose President Lincoln, President FDR, and Martin Luther King Jr.