Which of these is the best definition of an era?* A period of time identified by political, economic, or social trends
A series of various changes over many years
A series of events unified by individual or organized protests
A period of time lasting between 10-15 years

Brainliestttme : ) why was the launch of sputnik in 1957 important? -most in the u.s. had not thought the soviets were capable of producing satellite technology. - it made clear that the u.s. space program was dominant. - most in the soviet union had not thought the u.s. was capable of launching manned aircraft. - it established the fact that a more dangerous hydrogen bomb could be created.

Why was the land in the middle colonies attractive to immigrants

Mid to high level clouds that look like layered blankets are called