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?
You throw me out when you use me and take me in when you are done.
I have feet on my head
When it comes to me you go on red and stop on green.
I am the only thing that always tells the truth. I show off everything that I see. I come in all shapes and sizes. What am I?
Soldiers fight it but never changes.