No
No
ALL OF THEM. Handguns are illegal.
negative.
no they can not
yes
no no no no no no no no no no no no no no lololololololololollololollo
No
Yes
No they are not.
yes
Laws vary from state to state. In MOST states, there is no "registration" of firearms as such. If you live in a state that DOES require registration, then yes, that would be illegal.
Impossible to answer without knowing what you mean by illegal handguns.