How do I tell if the hot water in my apartment is gas or electric?

So I moved into this apartment like 6 months ago. I turned on the electric. I never turned on the gas because I thought it was unnecessary I dont live anywhere terribly cold and I dont cook often and if I do its in a Crockpot. So I thought Id avoid the unnecessary expense. (I didnt want to be tempted to use the gas heat so I thought this was a good idea) The hot water has been fine until today when it stopped working. I wasnt told by the apartments weather the hot water was gas or electric and up until today I assumed it was electric.Could I be wrong? Would the hot water have worked all this time if it was gas?