Describe the effect the invaders had on medieval europe

Why do countries create guidelines and laws on how a country is going to be run?

Who founded the social contract theory of the government

The telegraph, the transatlantic telegraph cable, and the telephone were important to businesses after 1850 because of a. they created a system for developing new inventions. b. they filled a need that other inventions of the day could not. c. they attracted investors and created the stock market. d. they made picture-taking a popular american pastime.