Ground water is:
1)stored in porous soil and rock
2)part of the nitrogen cycle
3)reduced by respiration
4) unavailable to plants

Avariable that is positioned between the independent variable and the dependent variable but does not interact with either to affect the relationship between them is called a variable. select one: a. moderating b. spurious c. mediating d. causal

Among the following environmental factors, which does not have a long-term impact on the composition of a region's soil? a. kinds of crops grown b. types of fungi present c. topography of the landscape d. variety of species of mammals e. number of freezes occurring annually

In 2009, roughly of people age 12 or older who did not drink alcohol were current users of illegal drugs. a. 4% b. 10% c. 13% d. 20%