Subject: Lifespan of HIV in contact with air?

Question: Is it true that when aid/hiv virus is in contact with air
it instantaneously dies? How long does it live in droplets of
water or semen that is in contact with air? What happens for
example in a scenario where person has aids has a cut on his
finger where some of his blood is dropped on a particular book
cover. Time passes and the blood stain on the book is dried up.
The next person who also coincendently also has a cut on his
finger and the cut comes in contact with dried up blood stain
on the book? What are his chances of him getting Aids/HIV?
What are the chances of one getting HIV from a toilet seat that
has been left for sometime and the next person sits on
it has the tip opening of his penis touch the toilet seat
(that has been stained with semen or water)? Would it be
possible for the virus to go through the lining inside of the penis
if contacted between semen on the toilet seat and semen from
the penis (taking consideration if / if not the semen or water
droplet on seat have been dried up or not?)

Thanx ( I know a lot of questions to ask from a paranoid person)
Mike

Re: Lifespan of HIV in contact with air?