Answer:
I am whole but incomplete. I have no eyes, yet I see. My largest part is one fourth of what I once was. What am I?
I build bridges of silver and crowns of gold. What am I?
I always have to work with something in my eye. What am I?
my rings are not worth much but they do tell my age.
Who keeps the ocean clean?
No matter how little or how much you use me, you change me every month.