What number should come in place of the question mark below?

What is the Surname of Barbie Doll?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

Two men are in a desert. They both have packs on. One of the guys is dead. The guy alive has his pack open, and the guy who is dead has his pack closed. What is in the pack?

Can you solve the maths in the below-given picture equation?

How many sides does a circle have?

A car meter reading shows 72927 miles a palindromic number.
what is the minimum number of miles you would need to travel to see another palindromic number on the car meter reading?

Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.

How will you do it?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

One night, Louis and Adam were sitting together. Adam was watching a movie while his wife Louis was reading a mystery book. Suddenly the power went out and Adam decided to go to bed, but strangely Louis kept on reading. There was no artificial light around, so Louis kept on reading. How come?