About 3-4 months.
No, you can pluck the feathers from the birds, but it would be VERY painful for the bird and you couldn't pluck all the feathers from the bird because that would leave nothing to grow back.
No the just grow back normal and will eventually grow back to normal and you have to pluck them about every 5 to 6 months or some peoples grow faster than others but no they dont grow back spiky.
Yes they will grow back.
They will grow back as normal eyebrows.
24 hours
no, the same amount will grow back after a week or so.
yes it will, it just wont grow back as thick as if you were to shave them.
yes it could grow back.
yes they do, but if you pluck them too many times they wont
yes
Of course, that's why people pluck them, to stop hairs growing back where they don't want them to.
you will grow it back in about 5-7 days