Maria is 30 years old and earns $75,000 per year. She has been saving $6,000 per year for several years since she graduated from UNH. She accumulated $18,950 already. She plans to work till age 65 and retire. She plans for a 25-year life after retirement. She desires an annual income of $50,000 during retirement. Assume interest rate is 4%. a) If Maria continues to save $6,000 per year, would it be enough for her plan? If not how much more/less should she save? b) Assume in addition, Maria desires to buy a boat 10 years after her retirement and enjoy the aquatic activities along the shores. The boat is expected to cost $25,000. Also Maria wants to leave $20,000 for charity at the end. How much should she save every year under this plan? c) Assume the plans in part (b). What interest rate must Maria earn for her to achieve her plans and continue saving just $6,000 per year?