(a) A savings account promises to pay 4% compounded annually. If you deposit $500 in the account today, precisely how long will it take for the money to reach $1,000? That is, how long will it take for your money to double?

(b) Using the same information from (a) and the rule of 72, how long will it take for your money to double (Goggle Investopedia Rule of 72 if you need to)?