The independent variable is what will change. The dependent variable is what will change because of the independent variable. The controlled variable is what will stay the same.
Ex, for the first one.
IV: the amount of sunlight
DV: plant growth
CV: pea plant
For #2.
IV: the soda
DV: the amount of sugar
CV: soda
And so on
<em>Please</em><em> </em><em>see</em><em> the</em><em> attached</em><em> picture</em><em> for</em><em> full</em><em> </em><em>solution</em>
<em>Hope</em><em> </em><em>it</em><em> helps</em>
<em>Good</em><em> </em><em>luck</em><em> on</em><em> your</em><em> assignment</em>
<span>I think that inhalants are a delivery method and not necessarily a drug type. The other three listed are actual drug types and are used in physical and mental health prescriptions. Inhalants are typically non-prescription/illegal drugs.</span>
Answer:
The population is people who buy mystery novels at that specific book store.