Does a teaspoon of honey before bed really calm a child's cough? To test the folk remedy, pediatric researchers at Pennsylvania State University carried out a designed study involving a sample of 105 children who were ill with an upper respiratory tract infection (Archives of Pediatrics and Adolescent Medicine, Dec. 2007). On the first night, parents rated their children's cough symptoms on a scale from 0 (no problems at all) to 30 (extremely severe). On the second night, the parents were instructed to give their sick child a dosage of liquid "medicine" prior to bedtime. Unknown to the parents, some were given a dosage of dextromethorphan (DM)-an over-the-counter cough medicine-while others were given a similar dose of honey. Also, a third group of parents (the control group) gave their sick children no dosage at all. Again, the parents rated their children's cough symptoms and the improvement in total cough symptoms score was determined for each child. The data (improvement scores) for the study are shown in the table below.
a. Construct a dot plot for the coughing improvement scores for the 35 children in the honey dosage group.
b. Refer to part a. What coughing improvement score occurred most often in the honey dosage group?

Based on Paul, I. M., et al. "Effect of honey, dextromethorphan, and no treatment on nocturnal cough and sleep quality for coughing children and their parents." Archives of Pediatrics and Adolescent Medicine, Vol. 161, No. 12, Dec. 2007 (data simulated)