First, the calculation of interest is simple, and it is quite zero deposit and withdrawal.
Principal plus five-year income = 500 * (5 *12+1)/2 * 5 * 4.12%+5 *12) = 33141.
Second, the calculation of compound interest, the money fund carries forward the income every month.
Principal plus income of fixed investment = 500 * (1+4.12%/12) * (1-(1+4.12%//kloc-0).
The above answers, I hope to help you.