Why was the us able to stay out of the war for so long? why did they want to stay out of the war?

If you mean WW2, its because America wanted isolationism and didn't want to fight in the war.  They were able to stay out of it for as long as they did because they didn't take sides.

answer is b.

  it is always the best policy to have good communication and good relations between individuals and, specially, between leaders of the countries. for this purpose, among others, there is a common place, the united nations, where the representants can present his and learn about the other country's policies.

how is this a question? but yes, they were. if i recall correctly, it was very handy for native americans to use buffalo skin.