Why did the underground railroad run all the way to Canada and not simply in the northern free state?

What were some of the new consumer appliances that americans could purchase in the 1920s

At the time of the brown v. board of education decision,schools were segregated everywhere in the country.several states had laws requiring segregated schools.schools in nearly every state has been desegregated.segregation was common in the north, but not in the south.

Debris tossed into the atmosphere by a meteorite impact can cause greenhouse warming true false