2. a) If every year you invest 15% of your annual income at 8%, after 30 years, how much, in terms of your annual income, will you have saved? b) If you require 80% of your annual income to retire, how many multiples of your annual income must you have ready to invest at 4% if you assume youll live 40 years after retirement? c) Based on your answers to a and b, is a an effective retirement plan? Assume the annual income remains constant, and ignore inflation for this problem.