Who is that with a neck and no head, two arms and no hands? What is it?

Yesterday I fell from 30 feet high ladder but I don't get hurt. Why?

A four-digit number (not beginning with 0) can be represented by ABCD. There is one number such that ABCD=A^B*C^D, where A^B means A raised to the B power. Can you find it?

What kind of band never plays music?

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

A man is walking down a road with a basket of eggs. As he
is walking he meets someone who buys one-half of his eggs
plus one-half of an egg.
He walks a little further and meets another person who buys
one-half of his eggs plus one-half of an egg.
After proceeding further he meets another person who buys
one-half of his eggs plus one half an egg. At this point, he
has sold all of his eggs, and he never broke an egg.
How many eggs did the man have to start with?

I know a nine-letter word having only one vowel.
Do you ?

What always comes into a house through the keyhole?

No matter how little or how much you use me, you change me every month. What am I?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?