Or I like to blow smoke up everyone's tailpipe.
Its one of those three, but I'll let everyone take their own guess as to which one it is.
I actually worked for a petroleum services corporation that did field maintenance, installation of pumps, and repair (electrical componentry, displays, calibration meters, digital meters, etc)
We also installed point of sale systems inside the store (Ruby Verifone, Topaz touchscreen, Wayne Nucleus, Gilbarco G-Sites, etc)
Basically, I was responsible for the upkeep of everything from the "cash register" back to the back office, then underground to the pumps outside and inside the pumps (on the electrical side). Then I was responsible for the hydraulic side from the pumps, to the underground storage tanks (UST's) and vapor vent piping, vacuum pumps, flare stacks, etc. I was fortunate enough to learn quite a bit. From all of the above, to how to
actually get free gas (and how to actually get arrested, mind you! lol)
Pair that with my years in the Navy as an Electronics Technician, working on High Frequency Transceivers and amplifiers, and radar propogation (basically, if it used electricity, I was expected to not only know HOW it worked, but how to either repair any component in it, or build an entire other piece!) and I was able to derive some knowledge in the fields of both consumer end electronics, and corporate/industrial scale pieces.