The launch of Sputnik / stunned Americans
because
The United States had landed the first man
on the moon.
The USSR had landed the first man on the
moon.
The USSR had launched the world's first
artificial satellite
The United States had launched the world's
first artificial satellite.

The USSR had launched the world's first

artificial satellite.

Explanation:

world war i began in 1914, after the assassination of archduke franz ferdinand, and lasted until 1918. during the conflict, germany, austria-hungary, bulgaria and the ottoman empire (the central powers) fought against great britain, france, russia, italy, romania, japan and the united states (the allied powers). to new military technologies and the horrors of trench warfare, world war i saw unprecedented levels of carnage and destruction. by the time the war was over and the allied powers claimed victory, more than 16 million people—soldiers and civilians alike—were dead.

explanation: