@roger,
Always a pleasure to chat with you, I have three weeks off and there is a ton of snow, so I'm just reviewing lesson plans and pestering the wife and stuff.
I teach:
C = Q/V
W = ½ QV
C = er e0 (A/l)
(1/C) = (1/C1) + (1/C2) + (1/C3) series
C = C1 + C2 + C3 parallel
and stuff.......