What does the trade deal vasco da gama made in india demonstrate about some of the motivations for exploration?

What was the importance of the open door policy?

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.

Which event to improve foreign relations between the united states and china?