a) What percent of patients in the treatment group experienced a significant improvement in symptoms? What percent in the control group?
For the treatment group is 66/85 ≈ 0.776 = 77.6%.
For the control group it’s 65/81 ≈ 0.802 = 80.2%.
b) Based on your findings in part (a), which treatment appears to be more effective for sinusitis?
The control group.
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?
The difference is small, so it seems it can be due to chance.