Use PMT equals StartFraction Upper P left parenthesis StartFraction r Over n EndFraction right parenthesis Over left bracket 1 minus left parenthesis 1 plus StartFraction r Over n EndFraction right parenthesis Superscript negative nt right bracket EndFraction to determine the regular payment​ amount, rounded to the nearest dollar. In terms of paying less in​ interest, which is more economical for a ​$170 comma 000 ​mortgage: a​ 30-year fixed-rate at 8​% or a​ 20-year fixed-rate at 7.5​%? How much is saved in​ interest? Question content area bottom Part 1 Select the correct choice below and fill in the answer box within your choice. ​(Do not round until the final answer. Then round to the nearest thousand​ dollars.) A. The​ 20-year 7.5​% loan is more economical. The buyer will save approximately ​$ enter your response here in interest. B. The​ 30-year 8​% loan is more economical. The buyer will save approximately ​$ enter your response here in interest.