1. There is a growing concern among many economists that income inequality has increased sharply since the early 1980s. A. How is income inequality measured? Please define three possible indexes of income inequality, including the Gini coefficient, and explain their usage. B. Has within-country income inequality increased in the developing world since the early 1980s? What is the evidence on this? C. In their article, C. Lakker and Branko Milanovic, "Global Income Distribution: From the Fall of the Berlin Wall to the Great Recession," World Bank Economic Review, Vol. 30, No. 2, 2016. 203-232, find that the gains in income globally since the late 1980s appear to follow what many have called an elephant shape. Please explain what the "elephant" shape means in terms of who has gained the most in income in the world since the 1980s. What factors may have caused the elephant shape