Exactly one of Al, Ben and Cal is a knight and the remaining two are liars. They are conversing among themselves about Dan who is a common friend of the three of them. They say:

Al
Dan has more than a million dollars.

Ben
No, Dan has less than a million dollars.

Cal
But, surely Dan has at least a dollar.

Who is the knight? Who are the liars? How much money does Dan actually have?

*** This puzzle has at least two solutions.