There are 529 athletes on the 2012 US Olympic team. There are 268 women and 261 men.
530
216
215.
Yes, people that play for the NHL-USA can still play for the Canadian Olympic team. (Sydney Crosby, Pittsburgh Penguins/ Team Canada)
About 1,000,000 athletes.
Yes the US Virgin Islands has an olympic team.
3
The United States Olympic Committee sent a total of 530 athletes.
45
Zero
It depends on what country you are talking about. The 2008 US Olympic rowing team had 45 members.