Who winnin rn trump or biden

What is a mechanism by which organisms maintain homeostasis when the level of one substance influences the level of another substance or the activity of an organ.

Isaw him _ .(a)danced (b)dance (c)dancing

During the revising stage in the writing process, the author freely explores topics for further inclusion in the work polishes the writing, fixing minor grammatical errors gets his or her ideas down in roughly the form he or she intends corrects major errors and improves the work's content