A mountain chart is a creative way to display the distribution of a quantitative variable over different categories. The overall distribution is shown as a smoothed histogram, and the area underneath is colored  according to different categories. The distribution of the variable for each category corresponds to the size of its colored area. The Gapminder software includes a mountain chart that shows the distribution of income broken down by world region and country (http://www.gapminder.org/tools/mountain). Click the play icon to see how the mountain chart changes from 1800 to present day, then answer the following questions:

(a) Extreme poverty is defined as living on less than \(\$ 2\) a day. In 1970, the majority of people living in extreme poverty came from which world region?

(b) In 2015, the majority of people living in extreme poverty came from which world region?

(c) Describe the shape of the worldwide distribution of income in 1970. In 2015.