She can spend c) $64.932 each year after she retires.
Explanation:
Calculate the accumulated sum after 30 years by using below formula:
S = R[(1+i)^n - 1]/i
Where,
S = the accumulated sum
R = the yearly deposit
i = the decimal interest rate per year
n = the total count of deposits
This results in a sum accumulation of $723,796.
Now calculate annual payout for a 25-year old annuity by using below formula:
R = Pi/[1 - (1+i)^(-n)]
This gives the PMT of $64,932.