Answer:
There is 10 birds on a branch, a man shot 5 of them. How many were left?
The thinkers usually hold this body part
There is one in every corner and two in every room.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.
I occur twice in eternity. And I'm always within sight.
It is something you will never see again.