2-37. Suppose a deposit of R dollars is made at the end of each year, and assume an APR of r% compounding continuously. (a) If we invest like this for 3 years, what is the value of the account after the third year? (b) If we are making these payments for 3 years, how much money must we invest today to cover the payments? (c) If we make these payments in perpetuity, find a formula which describes the amount of principal we must invest today to cover all future payments. (d) If we invest like this for three years, but instead use an account with an APR sfe compounded weekly, determine s so that this second account has the same value as your answer in part (a) after three years