Question

learning the language of scientific investigation
activity 2 of 6: variables
headache relief
a pharmaceutical company wants to test a new drug. they believe it will help in reducing the frequency of migraines. researchers gather two groups of one hundred migraine sufferers. the first group is given the new drug. the second group, however, is given a placebo—sugar pills. neither group knows whether or not it has
identify the dependent and independent variables of this experiment.
independent variable
select...
the placebo
the migraine sufferers
the new drug treatment
the frequency of migraines

Explanation:

In an experiment, the independent variable is what the researcher manipulates. Here, the pharmaceutical company is giving either the new - drug treatment or a placebo. The dependent variable is the outcome that is measured, which is the frequency of migraines. The migraine - sufferers are the subjects of the experiment.

Answer:

Independent variable: the new drug treatment, the placebo
Dependent variable: the frequency of migraines