Adouble-blind study of a vaccine is one in which : the study group receives the vaccine and the control group receives a placebo. neither observer nor subjects know the nature of the placebo. neither observer nor subjects know which subject receives the vaccine and which receives a placebo. neither the study group nor the control group knows the identity of the observers. the control group does not know the identity of the study group.

Melissa lives in a town called greendale. she discovers that when she lights a match and holds it near her kitchen faucet, the little flame grows into a larger fire. melissa is surprised because she thought the water would extinguish the flame rather than ignite it further. her mother tells her that the water might be contaminated with dissolved methane, a primary component in natural gas. melissa investigates the matter and finds that cases of methane contamination started shortly after a company began fracking for natural gas in the area. based on this information, which three statements are plausible consequences of fracking in greendale?

Many animals cannot sweat to maintain a stable body temperature. what is one other way animals can cool down?

Drag each label to the correct location. each label can be moved more than once match the properties with the subatomic particle