What does it cost to travel across America on a Greyhound bus?

I live in the England. How much does it cost to travel from the East Coast to West Coast of the United States on a Greyhound bus. Starting for example at New York city and travelling to Los Angeles.What does it cost to travel across America on a Greyhound bus?try this link: http://www.greyhound.com/home.aspWhat does it cost to travel across America on a Greyhound bus?9 billion