[math] \newcommand{\NA}{{\rm NA}} \newcommand{\mat}[1]{{\bf#1}} \newcommand{\exref}[1]{\ref{##1}} \newcommand{\secstoprocess}{\all} \newcommand{\NA}{{\rm NA}} \newcommand{\mathds}{\mathbb}[/math]

Plot a bar graph similar to that in Figure~\ref{fig 9.61}

for the heights of the mid-parents in Galton's data as given in Appendix~B and compare this bar graph to the appropriate normal curve.