Yes.
Yes. You can marry your LIVE wife's sister if you want to, provided that you are both free to marry.
Your wife's brother is your brother-in-law.
My wifes brother in law!
Your sister in law is your husband's sister or your brother's wife.
You're wife's brother's wife is your sister-in-law.
i believe that your brother's wife's sister is also your sister in law No, I think not! But as you seem to have the hots for your brother's wife's sister, you can call her "honey" if you like.
You would call your wife's elder brother's wife "sister-in-law."
Josephine and marry
No reason why not - they are only related by him previously being married to her sister - they are not blood-related. Except that if the woman is his widow then the guy is dead already and unable to marry anyone. If you meant his late wife's half sister then yes he may legally marry her, provided she wants to marry him of course.
Probably your niece-in-law.
Your half-brother...