A Magic Hexagon

In the figure, place the numbers 1-12 at the locations a-l such that each side has the same sum. There are possibly many solutions. Can you find a solution for each possible common sum?

To aid in comparisons, when submitting answers, minimize 'a', then 'b'.

  a b c
 l     d
k       e
 j     f
  i h g 
Source: Submitted by Gabe Sebo.
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