What essential characteristic(s) does a good experiment have? A. A control group is given the experimental treatment.

B. A single variable is tested.

C. A control is used.

D. Both b and c

Which continents lie only in the northern hemisphere

Acontinental polar air mass foms in

Read the article titled "does the family farm really matter? " what reasons does this article suggest are the causes of the movement away from family farms to larger farms? (site 1 someone fast