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Areas
Annulus Area
 An annulus is the region lying between two concentric circles

Annulus Area
 Area = $\pi\;(R^2\;-\;r^2)$

 Find the area of the shaded region: Area = $\pi\;(R^2\;-\;r^2)$ R=6 and r=2 Area = $\pi\;(6^2\;-\;2^2)$ = $\pi\;(36\;-\;4)$ = $32\pi$

Find the area of the annulus whose radius are 2 and 7

Take $\pi=3.14$
Area=