please show manual calculation process and not just an excel sheet, would be much appreciated !

1. An investment of $500 is made at the end of the first year, $1000 at the end of the second year, $700 at the end of the third year and $100 at the end of the fourth year. Spot rates are si = 2.5%, 52 = 3.0%, $3 = 3.5%, and s4 = 4.0%. (i) What is the present value A and the accumulated value of these investments? Answers: A = $2147.24 and S = $2432.76 the end of the fourth year, what annual yield rate is earned over the four year period? Answer: 3.10% (ii) If someone invests the present value A at the beginning of the first year and receives in payment these four investments, what annual rate of interest has he or she earned over the four year period? Answer: 3.23% (iv) If the amount A is invested at the beginning of the first year and the amount S is returned at the end of the fourth year, what annual yield rate has been earned over the four year period? Answer: 3.170%