Why were most slaves concentrated in the south and southeast region of the united states

How did african americans the union during the civil war? a. by serving as representatives in congress b. by enlisting in the military to fight c. by organizing massive slave revolts in the south d. by negotiating for peace with the confederacy

Which event occurred in 1943 and to make the allied victory possible choose all answers that are correct

Only 1 vote per state regardless of size why is this a problem