Depends. Sometimes seconds or minutes. Worst case even a hour. If the egg is larger than normal compared to body size. Then it normally makes it harder on the hen.
It's hatch, and about 30 days.
15 days to 1 month
21 - 23 days
about 21 days
21 days, give or take a few days.
They most likely will not hatch at all.
It takes around 21 days for the egg to hatch the chicken. You can find more info regarding this cycle on following page: http://chickscope.beckman.uiuc.edu/explore/embryology/
The egg, 1st of all because there were eggs long before birds, but if you mean a chicken's egg then it is still the egg. This is because when a new species evolves, the egg is say, given birth to a sub-chicken, and the new species (chicken) is inside the egg, which is techically now a chicken's egg.
Ushally it will take a chicken about 1 or 2 days before another egg is layed but if you let kids and dogs and other animals chase the chickens it will be stressed out and it will take longer for the chicken to lay an egg which is about up to 3 or 4 day to lay another.
The actual formation of the egg inside the chicken takes about 24 hours, but when they sit down to lay the egg it can take anywhere from 15 minutes to a couple of hours.
Nothing, as long as it is not rotten, it is just like eating a chicken egg. A chicken is a bird.
No because they take the egg away from the chicken before it can be in the proper conditions to hatch.