The theory of color vision proposed by Ewald Hering that is based on three systems of color opposites is called the theory

Answer and Explanation:

In 1892 he proposed the color theory in which he thought that the colors red, blue, green, and yellow are special because he thought that any other color could be a mix of the colors and they exist in different pairs.

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for many centuries, the catholic church has been a patron of the arts. the church has used various scientific methods to maintain its power.

not 100% sure though!

ive noticed that too but is this a question