Jeff wrote:

All the definitions are equally valid.

You seem totally incapable of differentiating between a definition of a
quantity and a formula that links that definition to another quantity.

Further discussion seems pointless.

You seem totally incapable of understanding that ALL the equations are
equally valid, that NONE of them is the formal definition, and that it
is irrelevant WHAT the formal definition is as long as the equations
are valid.



--
Jim Pennino