You are given the following information about accounts A and B: (i) The amount in account A at time t is given by the amount function, A(t) = t 2 + 5t + 100. (ii) The amount deposited in account B at time 0 is 225, which accumulates at a simple interest rate of 8% per annum. (iii) The amount of interest earned by account A during the n-th year equals the amount of interest earned by account B during the n-th year. Calculate the effective rate of discount for account A in the n-th year. The answer is 9.8 percent, but how to get to that answer?