Which variable is the one that is adjusted by the esperimenter?

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation

the answer is c most of the fortnite players usually buy v bucks to get the battle pass and other cosmetics but some players who are referred to as "no skins" don't   buy skins and are usually noobs.

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?