# Donut & Tea

Calculus Level 4

A donut with hollow circle of radius $$r$$ and cross section circle of radius $$r$$ is shaped along with 3 copies of series of cuboids with height $$2r$$ and square-bases with decreasing side of $$\dfrac{2r}{n}$$, where $$n$$ is a positive integer.

As $$n$$ approaches infinity, the cross section from the top will tend to a T-like base as shown above.

Which figure would have more volume as $$n$$ reaches infinity?

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