The drug Ziac is used to treat hyptertension. In a clinical test, 3.2% of 221 Ziac users experienced dizziness (based on data from Lederle Laboratories).
a. Construct a 99% confidence interval estimate of the percentage of all Ziac users who experience dizziness.
b. In the same clinical test, people in the placebo group didn't take Ziac, but 1.8% of them reported dizziness. Based on the results from part (a), what can we conclude about dizziness as an adverse reaction to Ziac?