1. How long will it take $2,000 to reach $6,400 when it grows at 11 percent per year? (Do not round intermediate calculations. Round your final answer to 2 decimal places.)
2. Determine the interest rate earned on a $3,200 deposit when $3,800 is paid back in one year. (Round your answer to 2 decimal places.)
3. Approximately how many years are needed to double a $500 investment when interest rates are 10.25 percent per year? (Round your answer to 2 decimal places.)