According to Danto what is the difference between “imitation”, “impersonation”, and “illusion”? And why is this important for things like “all white paintings”?

After reading “The Transfiguration of the Commonplace,” by Arthur C. Danto.
According to Danto what is the difference between “imitation”, “impersonation”, and “illusion”? And why is this important for things like “all white paintings”?