Using the rule of 72, determine

5. Ron and Amie invested $5000 in an educational savings fund for their daughter when she was born. They were never able to add anything else to the account. What was the rate of return if they had $10,000 in the account after 12 years? 6. Kari would like to save $10,000 for a down payment on a house. Illustrate the difference in years it will take her to double her current $5,000 savings based on a 6%, 12%, and 18% interest rate. 7. What annual interest rate will cause your money to double in four years