Confused dude, and by orders of magnitude, dude

[WeAreAs1 at aol.com]

Hello Listvolk,

A quick 'n' dumb question:

When entering capacitor values into formulas which call for values of R and C,
are basic "C" units expressed as microfarads or farads?  For example, when
solving for cutoff frequency in a classic 3-opamp state-variable filter, the
formula is given as:

                  1
Fc = _____________
          2 * pi * R * C   

Obviously, R is expressed in Ohms, but is C expressed as Farads or
Microfarads?  That is to say, if my chosen cap value is 0.1uf, should I enter
C as 0.1, or should I enter it as 0.00000000000001 ?

Also, it is assumed that all formulas requiring a C value will adhere to this
definition of C?

Anxiously awaiting in breathless ignorance,

Michael Bacich