Sandy is planning for retirement given the following information: - Sandy will retire in 40 years (' n ' during working years). - Sandy will live for 20 years after retirement (' n ' during retirement years). - Sandy needs $430,000 y year income during retirement years (CF during retirement). - Sandy expects to be able to earn 18% return on investment during your working years ( r ' during working years). - Sandy expects to earn a 5% return on your investment during retirement years (' r ' during retirement years). 1. How much does Sandy need to have saved up at retirement? (PV annuity during retirement)