[Solved] What element or technique serves to unify and balance Raphael's School of Athens, an imagined dialogue among the great philosophers and scientists of classical antiquity? A) a symmetrical architectural setting of receding barrel vaults B) a foreground portrait of Michelangelo in the guise of a Greek philosopher C) the delicate treatment of the female nude D) the consistent use of vivid word-painting Slope: In mathematics and economics, the rate at which one variable changes over the change in another variable, often used in the context of supply and demand curves. Ovals: Simple, elongated round shapes that can be geometric forms in design or natural formations. Ratio: A quantitative relation between two amounts showing the number of times one value contains or is contained within the other. Negative Correlation: A relationship between two variables in which one variable increases as the other decreases, and vice versa.