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Is the following conjecture correct?
Conjecture:
If $A,B,C,D$ are four points in general position in the euclidean plane, with
$a:=\|C-B\|,\ \ b:=\|C-A\|,\ \ c:=\|B-A\|$
$a':=\|D-A\|,\ b':=\|D-B\|,\ c':=\|D-C\|$ ,
$\begin{align}
a+b+c\ &>\ a+b'+c',\ a'+b+c',\ a'+b'+c\\
...
