You are given the following information. X is the time-value at the end of year two of all payments from a 20-year annuity-due which pays 1 per year. The annual effective interest rate for year t is 1/8 + t Which of the summations given below is equal to the value of X? sigma^28 _t=9 10/t sigma^28 _t=9 1/t sigma^29 _t=10 10/t sigma^29 _t=10 11/t sigma^30 _t=11 10/t