a.)
1.) Mind reading or telepathy.
2.) Remote viewing.
3.) Predicting the future.
4.) Telekinesis.
b.)
This part of the question is a bit more complicated. For all the tests, ensure there is no foul play. Make sure the psychic, spirit medium, whatever, doesn't know any information about me. Must know something only I could know.
There is also a problem here on the testability of these phenomena, if they exist. Say spirits do exist, can we guarantee they will act on command? As an example, just because I can do a triple sommersault doesn't mean I have to. If someone wanted to verify that's possible, but I do not wish to act, how can my assertion be verified that I can indeed do a sommersault?