both 1970 and 1980, the difference in life expectancy
was between 7 and 8 years.
Look at each pair of data points
and find the difference in life expectancy for males and
females. You can estimate the difference from the graph
or measure it with a ruler. You can also use and index
card or a sheet of paper and mark the difference to see
which is greater. Then identify the years for which the
greatest difference occurs. The greatest difference (between
7 and 8 years) appears in both 1970 and 1980.