Assume the total cost of a college education will be $$300,000$ when your child enters college in $18$ years. You presently have $$63,000$ to invest. What annual rate of interest must you earn on your investment to cover the cost of your child$$s college education? $($Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$