hare krishna prabhujis and matajis

please accept my humble obeisances.

srila prabhupada ki jay.

my doubts are 

1)are parvatidevi or umadevi or durgadevi the same person?

2)is parvatidevi a demigod or not?

3)is durgadevi expansion of radharani?

 please give ur valuable replies.

                                                      ur servant

                                                          nitin