Which statement accurately describes the meaning of a valid study? A valid study is a plan for how data will be collected in order to answer a research question.
A valid study is a research question or hypothesis created in order to make a prediction.
A valid study is one which has accurate results true to its original aims.
A valid study is one which is easily replicated.

Smoking cigarettes is a pervasive habit found in many parts of the world and a habit that could be explained by both microsociological and macrosociological forces. give an example of each that would be relevant to explaining the proliferation of smoking. how might your suggested micro- and macro-level analyses be linked

Burns are devastating and debilitating because of loss of fluids and electrolytes from the body. how do physicians estimate the extent of burn damage associated with such dangerous fluid loss?

[120 total points] (public health) in one of the largest human experiments ever conducted, in 1954 a randomized controlled trial was run to see whether a vaccine developed by a doctor named jonas salk was effective in preventing paralytic polio. a total of 401,974 children (ages 6–9), chosen to be representative of those who might be susceptible to the disease, were randomized to two groups: 200,745 children (the control group c) were injected with a harmless saline solution (a placebo) and the other 201,229 children (the treatment group t) were injected with salk’s vaccine.what was the point of giving saline solution to the children who didn’t get the vaccine? explain briefly.