I think the answer might be B.
a control helps to increase the reliability of the results. it allows a scientist to compare it to other group(s) in an experiment. if a scientist notices a significant different btwn the control and the other groups, he can logically conclude that the independent variable has an impact on the dependent variable.
a variable is any factor, trait or condition that can exist in differing amounts or types. there are usually three tpes of variables in experiments: the independent, dependent and contolled. the independent variable variable is the one that is changed by the scientists to figure it's affect on something.
Answer:
Demeter International
Explanation:
Demeter International is the primary certification agency for farms and gardens using the methods. In the United States, bio-dynamic farming dates from 1926.-
Answer:
geologists use rock samples and direct evidence to prove what earth's structure is like.
Explanation:
