Assume the total cost of a college education will be $390,000 when your child enters college in 18 ycars. You presently haye $64,000 to invest. What annual rate of interest must you eam on your imvestment to cover the cost of your child's coliege education? Note: Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.9., 32.16