I can only answer 3 i cant answer 4
Answer:
Dollar Diplomacy
Explanation:
William Howard Taft and his secretary of state, Philander C. Knox, to ensure the financial stability of a region while protecting and extending U.S. commercial and financial interests there.
I think it c intersates,and highways
There was no unified state that could grow all parts of life equally so they had to depend on trade in order to get goods that they needed from each other since they couldn't develop all parts of production or manufacture. Ones would for example have a developed pottery industry while the others would have mastered making Olive oil so they would trade in order to get what they needed because they couldn't make it on their own.