I dont know how this could be possible. Having built buildings for 20 years I dont know of any way to wire or plumb one unit in such a way . How ever first things first.
She needs to first advise the super that some thing is wrong. Also she needs to contact the utility companys and get them to start investigation, and they will. Next contact a plumber / electrician, a licensed handy man or builder. Have the repairs done, and contact a lawyer to make the building management company pay all the expenses.

I have no faith in human perfectability. I think that human exertion will have no appreciable effect upon humanity. Man is now only more active - not more happy - nor more wise, than he was 6000 years ago. Edgar Allan Poe