What is the word or phrase?

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?

How could a baby fall out of a twenty-story building onto the ground and live?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

Which Burger Is Different in below image?

If a wheel has 54 spokes, how many spaces are there between the spokes?

Remove two matchsticks to make the below equation correct.

Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

10+10 and 11+11 can give you the same answer.

Explain how?