have you asked the fighters in the octagon or the pentagon? or did someone put a "hex" on your thinking stop sign?
best i can tell, all regular polygons have the same number of sides and interior angles
the district of columbia is a special case. it is not an actual state, and hence does not have senators or congressional representation. it is located between virginia and maryland on the potomac river.
it is on the potomac river between virginia and maryland and coextensive with the district of columbia. (dictionary)
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