This is one of the rare queries where I'd try Wolfram Alpha first: http://www.wolframalpha.com/input/?i=circumference+of+the+earth http://www.wolframalpha.com/

This is one of the rare queries where I'd try Wolfram Alpha first: http://www.wolframalpha.com/input/?i=circumference+of+the+earth http://www.wolframalpha.com/input/?i=circumference+of+the+ea...