Financial Mathematics questions, please answer both if you can. Will rate kindly, thank you!!

9. Greg receives uniformly continuous payments of $50 per year forever. The present value of this cash flow stream is $2500. What is the annual effective interest rate? 10. Halie receives $450 payments at the end of each year for 15 years, then after that $550 at the end of each year forever. The annual effective interest rate is 3.5%. What is the present value of this cash flow stream