Waiting period. Susan Norman seeks your financial advice She wants to know how long it will take her to become a millionaire. She tells you that she has $1,329 today and wants to invest it in an aggressive stock portfolio. The historical return on this type of investment is 21% per year. How long will she have to wait if the $1,329 is the only amount she invests and she never withdraws from the market until she reaches her $1 million? (Assume no taxes on the earnings.) What if the rate of return is only 16% annually? What if the rate of retum is only 8% annually