Answer:
I am useless when together but useful when I am broken apart. What am I?
Cold head and feet; round as a ball; always turning around myself.
I can be red blue purple and green. No one can reach me not even the queen.
I am a protector. I sit on a bridge. One person can see right through me, while others wonder what I hide. What am I?
I am a kind of coat that can only be put on when wet. What am I?
What never gets any wetter no matter how hard it rains?