A homeowner could take out a $30-$year mortgage at a $6\%$ annual rate on a

$$300,000$ mortgage, or she could finance the purchase with a $30-$year mortgage at a $5\mathrm{.}9\%$ annual rate with $1\%$ discount points. Which mortgage is a better deal? Will your answer change if the holding period is $15$ years? Show the dollar cost$/$savings$.$