Can you guys help me with B, I can't figure it out

Consider the cash flow transactions depicted in the accompanying cash flow diagram with the changing interest rates specified. I a $600 $600 $300 $300 0 3 1 5% Interest compounded monthly 2 8% Years Interest compounded monthly 6% Interest compounded monthly (a) What is the equivalent present worth? (In other words, how much do you have to deposit now so that you can withdraw $300 at the end of year 1, $300 at the end of year 2, $600 at the end of year 3, and $600 at the end of year 4?) The equivalent present worth is $ 1486. (Round to the nearest dollar.) (b) What is the single, effective annual interest rate over four years? The single, effective annual interest rate over four years is %. (Round to one decimal place.)