a) The equation r(C) = C/2 describe the relationship between the radius of a circle and its circumference. Since the area of a circle is given by A(r)= r², we can express the area as a function of the circumference by A(r(C)). Determine the simplified algebraic model of A(r(C)).

b) Use the technique in a) to determine an expression for the total area of a cube as a function of its volume. Represent the length of an edge by b.

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