The stem-and-leaf plot for the given data set is:
\[
\begin{array}{c|l}
1 & 2 \, 5 \\
2 & 2 \, 4 \, 5 \\
3 & 1 \, 2 \, 3 \, 5 \\
4 & 1 \, 2 \, 3 \, 4 \, 5 \, 6 \, 7 \, 8 \, 9 \\
\end{array}
\]
\(\boxed{\text{Stem-and-leaf plot constructed as shown above}}\)