Question: what is the theory of demamd and supply certain? 

Answer: remember when X box came out at Christmas and they were sold out overnight?\n\nOK the supply of X boxes went down \n\nBut \n\nEveryone still wanted them\n\nso    the demand for X boxes went up \n\nand people were selling them on E-bay for $2000 for a $300 product .. that's supply and demand.\n\n:)
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