Compound value solving for r) At what annual rate would the following have to be invested? a. $490 to grow to $1,270.93 in 10 years b. $330 to grow to $553.44 in 6 years c. $51 to grow to $834.69 in 20 years d. $216 to grow to $273.31 in 6 years a. At what annual rate would $490 have to be invested to grow to $1,270.93 in 10 years? % (Round to the nearest whole percent.)