thanks for any help. the mg functions were crazy so this is a picture of them typed up. thank you times a million for any help!
It should be clear that most of these are not valid moment generating functions because $\displaystyle M(0) \neq 1$.
So your job is to identify the ones that are valid and then consult a table to get the pmf. Once you know the pmf you should be able to answer parts (ii) and (iii). If you need more help please show what you'ev done and say where you're stuck.