Because The United States wanted to promote the spread of democracy throughout Latin America since their interest was involved
The Native Americans helped the French. The English were stealing the Native American's land and the Native American's felt that wasn't fair so they put their efforts and trust in the French. That is why it was called the French and Indian War because the French and the the Indians were allies and they fought together.
Diseases and insects would take out crops in less than a week, so tobacco farmers had to inspect their crops everyday. I hope this helped.