What is the role of the United States in the new century?

In the early 20th century, America was flexing its economic and political muscle on the international stage. The era was defined by the temperance movement, Progressive-era activism, the sinking of the Titanic and World War I.

Explanation:

It is also the role of united state in present century

1. where does the energy of a nuclear power plant come from?

d) political bosses should not hold office