What are four american inventions that revolutionized agriculture, manufacturing, and communications between 1831 and 1876

How did justinian attempt to revive the “glory of rome”?

Describe two observations that galileo was the first to make with his telescope.

What event started the space race and made americans feel their security was threatened a.) alan shepard's suborbital flight. b.) the launch of sputnik c.) the launch of explorer d.) the cuban missle crisis