Power of attorney my mother would like to complete a general power of attorney…

Power of attorney
my mother would like to complete a general power of attorney it shows it includes financial,health care & property. she would like to do this now, as she is healthy and well- my question is – is there a time limit once we sign and have it notarized – does it expire – if the document does not indicate a termination date- ? Would this be legal until as long as she was living?

power of attorney I have ”general power of attorney (with specific termination…

power of attorney
I have ”general power of attorney (with specific termination date)” of my finacee and I went to the bank this morning to get my name put on her account and they denied this form. Can they do that? There reasons were that it had a specific termination date and that it had a clause that stated that the form would be invalid in case of death, disability or incapacity, thus they couldn’t tell if she was either of the three. Could you tell me if they are in the right to reject this form and what can I do?

power of attorney”general” I was appointed power of attorney by my sister who…

power of attorney”general”
I was appointed power of attorney by my sister who was in state jail. How is power of attorney terminated? Can she appoint another person as power of attorney before terminating mine? What of my decisions can be challenged with a general power of attorney over all affairs.