A savvy investor paid $$5,500$ for a $20-$year $$10,000$ mortgage bond that had a bond interest rate of $8\%$ per year, payable quarterly. Three years after he purchased the bond, market interest rates went down, so the bond increased in value. If the investor sold the bond for $$11,500$ three years after he bought it$,$ what rate of return did the investor make per quarter and per year $($nominal$)?$ The rate of return per quarter is $\%.$ The rate of return per year is $\%.$

$25\mathrm{.}45$ and $101\mathrm{.}80\%$ are inccorect anwsers.