1. The problem asks to sketch polygons showing the distribution of test scores for two groups: students who studied printed pages and students who studied on a computer screen. 2. A polygon graph for a distribution connects points representing scores in order, showing the shape of the data. 3. The printed pages group scores are: $16, 17, 18, 18, 19, 14, 17, 17, 20, 15, 19, 16, 17, 13$. 4. The computer screen group scores are: $16, 14, 17, 13, 18, 17, 10, 17, 12, 16, 15, 18, 15, 19, 16, 14, 12, 15, 11, 13, 17$. 5. To sketch the polygons, plot the scores on the y-axis against their order (1, 2, 3, ...) on the x-axis for each group. 6. Connect the points for the printed pages group with a solid line and the computer screen group with a dashed line to distinguish them. 7. Observing the graph, the printed pages group generally has higher and more consistent scores, while the computer screen group shows more variability and some lower scores. Final answer: The polygon graph visually compares the two groups' score distributions, showing printed pages group tends to perform better and more consistently than the computer screen group.