What new learning were Europeans acquiring ?

Which of the following was the center source of energy during the industrial a revolution

For in this unit, you read about transitions of power and the formation of newly independent nations in africa, asia, the americas, and the middle east. some of these transitions were peaceful, while others caused long-term instability. why do you think some countries were more successful than others with political transitions? what do you think were the biggest challenges facing newly independent countries? would it have been possible for leaders to prevent these problems before they happened? why or why not?

Which would make the best heading for this list of notes about the migration of african-americans during the reconstruction era?