Your parents will retire in 17 years. They currently have $310,000 saved, and they think they will need $2,200,000 at retirement. What annual interest rate must they earn to reach their goal, assuming...

Your parents will retire in 17 years. They currently have $310,000 saved, and they think they will need $2,200,000 at retirement. What annual interest rate must they earn to reach their goal, assuming they don't save any additional funds? Round your answer to two decimal places.

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