Kennedy, king, lincoln | English homework help

Due in 45 minutes. Short Essay. Describe Kennedy, King, and Lincoln as speakers.  What do the voices in their speeches have in common?  What kind of argument does each voice present? Each of these people spoke to a specific situation and from a different experience, but are there still similarities between the voices? What are those similarities, and what do they tell us about the nature of the speakers and/or the nation?