1. True- because scientific theory means that <span>idea supported through research that attempts to explain existing observations or predict new ones.</span>2. False- because a cross-sectional means that its a study that is about different groups. 3. B-<span>An extraneous variable clarifies the relationship between the independent and dependent variables.</span>
hope this helps...prevention of childhood diseases and outbreaks, higher school attendance rates and lower occurances of diseases for families that may heave come in contact with children.
