For each person it's different; each person has a different heal rate.
There's a chance it won't heal, and there's a chance it might heal within a few days. You pretty much have to experiment and try for yourself.
About 10-15 minutes
It depends on where the piercing is. If it's in your nose then if will take a couple hours to close; if it's in your ear then probably a day or two.
Yes
It really depends on the type of piercing and long you've had the piercing.
It depends on how fast your body heals, and how long you have had the piercing. The longer you have had the piercing, the longer it will take to close. This is true for all piercings.
the hole will close over or it could get infected
yes its totally save to take a shower with your nose piercing in
It depends on where it is pierced. The lobes can take about 3 months to completely close up, where your cartilage can take 6 months to even a year to completely close up. It also depends on how long you have had the piercing. A piercing that you've had for years can take years to close (in my personal experience).
Yes it can. It all depends on your body. No real way to tell how long it would take.
a septum piercing never closes completly, sorry
you may NEVER take it out
It takes as long as it takes once a piercing has healed it depends on haow long you leave the jewellery out, if you are done with the piercing it can take a few days to several weeks for the piercing to actually close once it's a seasoned piercing (seasoned being over a year old).