help solve these problems please

1.-/1 points Smith receives $250 in 1 year, $500 in 2 years, $750 in 3 years and so on until the final payment of $2,500. Using an effective interest rate of 6%, determine the present value of these payments at time 0. Answer $ (round your answer to 2 decimal places.) 2.-/2 points Find the present at time 0) and accumulated value (at time 20) of payments of $35 at time 1 year, $50 at time 2 years, $65 at time 3 years and so on, up to the last payment at time 20 years. Assume an effective rate of interest of 8%. PV = $ (round your answer to 2 decimal places.) FV = $ (round your answer to 2 decimal places.) 3.-/1 points Find the present value of a perpetuity-immediate whose successive payments are $10, $20, $30, .... Assume an effective rate of interest of 8%. Answer = $ (round your answer to 2 decimal places.) 4.-/1 points An annuity pays $120 at the end of one month. It pays $135 at the end of the second month. It pays $150 at the end of the third month. The payments continue to increase by $15 each month until the last payment is made at the end of the 48th month. Find the present value of the annuity at 5% compounded monthly. Answer = $ (round your answer to 2 decimal places.)