Answer:
I'm a ruler with 12 agents. Half of them work in the darkness. Who am I?
My voice is tender my waist is slender and I'm often invited to play. Yet wherever I go I must take my bow or else I have nothing to say.
I am a bow that can never be tied or broken but can disappear. What am I?
Sometimes I am white, sometimes I am dark. Most people love me. What am I?
The Titanic is still here.
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.