Quote Originally Posted by JerMc
There's a lot involved with math for electronice: Ohms law, Formulas for reesistance. Trig, Imaginary numbers, non Euclidean Geometry, and quite a bit more. However, one thing I can tell you after nearly 25 years experience working with industrial instrumentation and electronics is after you get by the test, you generally use very little of it.
I know that. Shocking, isn't it?

Ruanaidh's link is very cool for the info, thanks. I'm not too bad with that, it's the math that was a problem. The Ohm's law formula first stages went well but to apply the answer into other parts of the question confounded me.
There's a faint hope of a retest. There's a better chance of the union encouraging the dep't to use their discretion. Just have to wait and see how the other testers do.