A study was done of honey as a remedy for coughing. The coughing improvement scores (as determined by the children's parents) for the patients in the over-the-counter cough medicine dosage (DM) group, honey dosage group, and control group are reproduced in the accompanying table. Complete parts a through d below. Click the icon to view the table of coughing improvement scores. a. Find the standard deviation of the improvement scores for the honey dosage group. The standard deviation of the improvement scores for the honey dosage group is 3.530. (Round to three decimal places as needed.) b. Find the standard deviation of the improvement scores for the DM dosage group. The standard deviation of the improvement scores for the DM dosage group is 2.134. (Round to three decimal places as needed.) c. Find the standard deviation of the improvement scores for the control group. The standard deviation of the improvement scores for the control group is . (Round to three decimal places as needed.) Table of coughing improvement scores Honey Dosage: 15 15 575 12 10 209 DM Dosage: No Dosage (Control): 519 22 12 629 12 337 9 06 11 82 12 855 15 345 13 14 10 13 036 10 96 8 11 13 12 2 134 O X 15 95 Full data set: 6 7 14 86 11 8 11 6 10 50 9 10 9 3 4 1 7 7 8 11