Why did some african americans decide to fight in the revolutionary war?

In the Revolutionary War, slave owners often let their slaves enlist in the war with promises of freedom, but many were put back into slavery after the conclusion of the war. In April 1775, at Lexington and Concord, blacks responded to the call and fought with Patriot forces.

the rebels’ chances of victory at lexington & concord were fairly slim, given the fact that most of them very untrained and they were up against the world's greatest military force.  

d

explanation:

it establishes america’s basic laws and fundamentals to its citizens.