1.2 Sinusitis and antibiotics. Researchers studying the effect of antibiotic treatment for acute sinusitis compared to symptomatic treatments randomly assigned 166 adults diagnosed with acute sinusitis to one of two groups: treatment or control. Study participants received either a 10-day course of amoxicillin (an antibiotic) or a placebo similar in appearance and taste. The placebo consisted of symptomatic treatments such as acetaminophen, nasal decongestants, etc. At the end of the 10-day period patients were asked if they experienced significant improvement in symptoms. The distribution of responses is summarized below.2 Self-reported significant improvement in symptoms Yes No Total Treatment 66 19 85 Group Control 65 16 81 Total 131 35 166 (a) What percent of patients in the treatment group experienced a significant improvement in symptoms? What percent in the control group? (b) Based on your findings in part (a), which treatment appears to be more effective for sinusitis? (c) Do the data provide convincing evidence that there is a difference in the improvement rates of sinusitis symptoms? Or do you think that the observed difference might just be due to chance