Austria-Hungary had invaded and crossed over into, Serbia and Russia was in an alliance with Serbia, so they felt as though they had to help out. Hope this helps.
No George Washington was not the only president to fight so its false other presidents also served in the military
The correct answer is increase in industrialization.
Due to the technological advancements of the mid-late 1800's, Americans started to rely more on industry rather than farming. Working in a factory rather than a farm had its perks. People who worked in a factory had guaranteed wages, whereas in farming the amount of money a person makes is dependent on several different factors like the amount of people who want to buy your products, climate, location, etc.
The protestant reformation divided western Christianity though it has been divided before
Answer:
Lack of Farm Production
Great Britain, Spain, Mediterranean Pirates