🚀 go-pugleaf

Can anyone give me an example of 2 regular (i.e. the derivative is never
zero) simple closed curves in the plane, which are infinitely many times
differentiable everywhere (absolutely NO corners or edges in derivatives
of ANY order), and who are not similar to each other, such that their
isoperimetric quotients are equal?
  The isoperimetric quotient is defined as =4*pi*A / l^2, where A is the
area that the curve bounds, and l is the arc length of the curve.

  An analogous problem is in space: Does there exist 2 closed surfaces
in space, which bound a volume, V, and has an area, S, an is infinitely
many times differentiable without exception, not similar to each other,
whose isoperimetric quotients are equal?
  The isoperimetric quotient is here = 36*pi*V^2 / S^3.