gold oil and the us dollar

The interaction of these three elements is a very special cocktail.
Im told that the US dollar is being bought because the currency traders are selling Euro and Pounds Stirling. They are not buying the dollar because of its fundementals ie strong economy and positive trade balance because infact the American Economy is the very opposit growing trade deficits and budget deficits.They are buying it becuase they are selling Euro and have got to put the money some where.

Im told that oil is falling because of falling demand. At $80 a barrell will this be the case- very unlikely. So how long will it stay at $80 before growth in developing countries replaces the shrinking demand and peak oil forces prices up again.

On the supply side how many goldmines operate at a profit when the gold price goes under $700 an ounce.