Your sister needs some advice on how to save for her retirement. She is 40 years old and she wants to begin saving for retirement with the first payment to come one year from now. She can save $5,000 per year; and you advised her to invest it in the stock market, which you expect to provide an average return of 9% in the future. How much will she have at 70? O a. 893,540 O b. 681,537 C. 435,600 d. 570,119