Jonas Salk is important for?

Cable cars, elevated steam trains, electric trolleys, and commuter trains eased the ability of people to live outside of major urban areas yet still work there.

The conference at Potsdam was tense because the: United States had dropped the atomic bomb. Soviet Union switched sides to the Axis powers. Allies were not sure of victory. Western Allies distrusted the Soviet Union.

What event caused congress to pass the brady bill?

What were the three racially motivated incidents in the 60s?

How did americans react to the miltary-industrial complex?

Which objects provided anthropologists with the first clues about prehistoric life?

What state or territory had the largest number of slaves in 1790?

Which turn-of-the-century political movement emphasized conservation?

For most of human history, what was the total population?

The person who wrote the declaration of the independence was ...