Who was the first person in modern times to explore the Colorado River and Grand Canyon? A: John Wesley Powell

B: William Clark

C: John Muir

D: Thomas Jefferson

What was the purpose for "checks and balances" in the government? it made possible a system of accountability. it would control the national bank. it would the states to work together to solve national problems.

What lands were added to the russian empire under ivan iv, peter the great, and catherine the great?

Once the plague became airborne, how could it then be spread?