For plane , there are at least
different distances . The minimum distance  can occur only maximum  distance 
 can occur distance  can occur as often as
times.
Finally, no set of plane  can determine only isosceles
 triangles .
 
See also Distance 
Explore with Wolfram|Alpha 
References Honsberger, R. "The Set of Distances Determined by Mathematical
 Gems II.  Referenced
 on Wolfram|Alpha Planar Distance 
Cite this as: 
Weisstein, Eric W.  "Planar Distance."
From MathWorld https://mathworld.wolfram.com/PlanarDistance.html 
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