#### Answer

a.) about the year 1973 at 15%
b.) about the year 1992 at 12%

#### Work Step by Step

a.) The green line represents the population under 18 years, and the blue line represents the population 65 years and above. They will have the same percentage of income below the poverty level at the point where the lines intersect. If you look at the graph you will see that the lines intersect at approximately 1973 on the x-axis and 15% on the y-axis.
b.) The blue line represents the population 65 years and above, and the red line represents the population 18-64 years. They will have the same percentage of income below the poverty level at the point where the lines intersect. If you look at the graph you will see that the lines intersect at approximately 1992 on the x-axis and 12% on the y-axis.