Answer
(a) this is an example of an experimental study. This means it has to compare two groups. One group gets the drug and one gets the placebo. The study is double blinded.
(b) this statement is an observational study. The researchers are collecting data from the subject by an observer.
Work Step by Step
(a) The two groups of patients who receive the medicine are unaware as to whether or not they are being treated with any medicine.
(b) The study observes babies weight and how it correlates alongside the income of the family.
