Henry and walter open savings accounts at the same time. henry invests $6,500 at 4.54% simple interest, and walter invests $7,100 at 4.74% simple interest. after eight years, how much more interest has walter earned than henry? a. $331.52 b. $420.67 c. $631.52 d. $719.59 please select the best answer from the choices provided a b c d