spiderman
A lot of comic writers like to make heroes look tougher by making them beat Spiderman, using him as almost a stepping stone. At first thought I'd personally say Spiderman though, unfortunately, the only time I can think of that they fought was during in the Civil War comics... Captain America won. They are both excellent fighters. I don't know what to tell you, but coming straight from the comic books, Cap seems to have the advantage (although I think they only made him win to make up for the crazy beating he took from Iron Man).
Wolverine, he's the best there is at what he does
well quite obviously spiderman. venom maybe more enhanced but its spiderman. he's beat venom more than venoms beat spiderman.
Captain America! Black Widow might be agile and quick, but Captain America is super strong and has that unbreakable shield.
PRICE
Without Nuclear explosives North America would still win. North America has better technology, men who are superiorly trained and is much richer than South America.