Answer:
Friction between the wheels and track causes energy to leave the system in the form of heat.
Explanation:
the last sentence is the one I think
Answer:
The first slaves were brought to the Americas in 1619, when 20 men from Africa were brought to Jamestown, VA. Historians are not sure whether this was the true beginning of the legal slave trade in the colonies. Indentured servitude already existed in the region.
Explanation:
Puerto Rico is where is continued even after the Spanish forces surrendered in Cuba