What is at the end of a rainbow?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

There are 2 cops parked along a one-way street looking for traffic violations. They spot a taxi driver going in the wrong direction, yet they do nothing.

Why?

Which English verb becomes past tense just by rearranging the letters?

I have teeth but i don't bite. Who Am I ?

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

What can you catch but never throw?

People put me on the table and cut me but do not eat me. What am I?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?