You are correct and you caught me.Batteries.
I just spit orange juice all over my computer!!!!
You are too funny.
I was just trying to josh the City spin doctors who would come up with some bizarre response.
I am not good at this set theory or abstract math stuff.
I had my mind taxed over its limit with those higher order vectors called tensors and those Bessel functions. Partial differential equations almost did me in, but I sneaked by.