Which of the fallowing best explains the diff variation of coat color in species?

Why do we perceive objects as retaining their brightness under different lighting levels?

During an experiment, readings for blood pressure in a persons body were found to be constant . however , when he measured by a different blood pressure cuff , the readings differed by 15 points for each reading. this difference indicates that the results are

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes