A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

I look at you, you look at me I raise my right, you raise your left. What am I?

What is the Surname of Barbie Doll?

You are trapped in a room with two doors. One leads to certain death and the other leads to freedom. You don't know which is which.
There are two robots guarding the doors. They will let you choose one door but upon doing so you must go through it.
You can, however, ask one robot one question. The problem is one robot always tells the truth, the other always lies and you don't know which is which.
What is the question you ask?

How many letters are in the alphabet?

What you cannot hold but it is yours?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

When it is alive we sing, when it is dead we clap our hands. What is it?

What goes up but never comes down?