RIDDLE ME THIS, BATMAN

A MAN IS LOOKING AT A PHOTO AND SAYS, "BROTHERS AND SISTERS HAVE I NONE, BUT THAT MAN'S FATHER IS MY FATHER'S SON." WHO IS IN THE PICTURE?

A woman takes the elevator from her twelfth floor apartment to the ground floor and takes the elevator up to floor 7 and walks the other 5. Why?

Three lightbulbs in a room. Three switches and you in next one. How do you know which bulb is connected to which switch if you only leave once?

What demands an answer but asks no question?

In a room completely bricked on all sides with nothing but a mirror and a table, how do you get out?

Imagine you are in a cement room with nothing in it and no doors or windows or any visible way to escape. How do you get out?

I am taken from a mine, and shut up in a wooden case, from which I am never released, and yet I am used by almost everybody. What am I?