Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

What has many teeth, but cannot bite?

Which is faster, Heat or Cold ? Explain.

What is greater than gold but cannot be bought. it can never be sold and can earn if its sought. though it can be broken, it can still be fixed. for by birth it can't start nor by death it is ended.what am i?

What's the best place to go shopping in the ocean?

A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

Imagine you are in a room with no windows or doors. How will you get out?

What is the fastest way to double your money?

The horse jumps over the king.
Strangely there is absolutely no scratch on him.

Can anyone explain, how is this possible?