In terms of paying less in interest, which is more economical for a $$140,000$ mortgage: a $30-$year fixed$-$rate at $8\mathrm{.}5\%$ or a $15-$year fixed$-$rate at $8\%?$ How much is saved in interest? Use the following formula to determine the regular payment amount.

$PMT=\frac{P(\frac{r}{n})}{[1-(1+\frac{r}{n}{)}^{-nt}]}$

Select the correct choice below and fill in the answer box within your choice.

$($Do not round until the final answer. Then round to the nearest thousand dollars.$)$

A$.$ The $15-$year $8\%$ loan is more economical. The buyer will save approximately $ in interest.

B$.$ The $30-$year $8\mathrm{.}5\%$ loan is more economical. The buyer will save approximately $ in interest.