The letter B represents china
The U.S wanted to remain neutral, based on what Woodrow Wilson wanted, but after Germany started sinking U.S ships, they got included.
It would be yemen. they have very little resources.
The Ninth Amendment states, The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people.” It was designed to work with the Tenth Amendment to reinforce limits on the federal government
I believe that the answer is sixty thousand people. Hope this helped :)