Please help me solve this

An investor plans to retire in 35 years and wants to be able to withdraw $ 50000 at the end of each year forever with the first payment to be received at the end of the 36th year. When the investor retires she plans to sell her business for $ 200000. Interest rates are expected to be 5 % compounded annually for the foreseeable future. What is the size of the end of the year annual contributions that the investor must make to the retirement fund