I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

Who are the happiest people in IPL match?

In which direction should the missing arrow point?

Can you find out the total number of triangles in the given figure?

If your uncle’s sister is not your aunt, what relation is she to you?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

What demands an answer, but asks no questions

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

A kind heart person buy packed food at 3$/packet from United states and sells them at 1$/packet at Africa. After some time he becomes a millionaire.

How come the guy become millionaire ?

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?