Define medium, technique, and proportion

In a fine art context, "art medium" refers to the art materials or artist supplies used to create a work of art. Basically, it's whatever you use to make a mark upon a surface.     the manner and ability with which an artist, writer, dancer, athlete, or the like employs the technical skills of a particular art or field of endeavor. the body of specialized procedures and methods used in any specific field, especially in an area of applied science.    Proportion is the principle of art that refers to relative size. ... Most, if not all of the principles of art deal with how the elements art are arranged in a work of art. Proportion is largely about the relationship of the size of one element when compared to another.

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