What are some of the conclusions that economists have made about convergence? (check all that apply.) a. convergence can look different depending on what timeframe you choose. b. convergence has not been the same for poor countries as it has been for rich and emerging countries. c. africa has two of the fastest growing countries in the world, which has led to convergence in africa. d. africa has had the same convergence rate as the oecd countries in the last 60 years.