Some people like to gamble. Sometimes they cannot help it. Like these two guys. Let's call them Jack and Daniel.

Jack:
Do you want to bet that I can drink a mug of beer by the time you drink
a shooter of beer?

Daniel:
What? Are you out of your mind?

Jack:
I am not kidding. I start with two mugs. I drink the first one normally to prepare
my throat and when I put it down on the table, that is when we both hear the sound
of the impact, we go for it. And I bet you that, both emptied, my second mug
will hit the table before your shooter. I practiced it for years, and made a great
deal of money with this ability. I actually never failed and people are used to bet
a lot, because they just don't believe it.

Daniel:
Well I am one of them. I mean even if you can drink it way faster than average
people, I am also a fast drinker. So a tiny shooter like that, I just can't miss it.

Jack:
Think about it. Suppose that I can open my throat for the beer to go straight
through and that I could be faster than you taking too much time gulping.
Can you drink anything without having to swallow it?

Daniel:
No, I can't. But I know it is possible. A sausage eater beat the world record simply
because he didn't take the time to chew them! The sausages went right through
the throat. However in this case my friend, I don't think you can drink a mug by the
time I drink a shooter. It is just physically impossible, so I am willing to bet a lot on it.

Jack:
Trust me, it is physically possible. If you accept the challenge, there is only one
simple rule: nobody is allowed to touch anything but his own glass, and only when
we hear the sound of my first mug hitting the table. Then with our right hand ready,
we get a move on! With the slight advantage of not having any reaction delay,
I bet you a blank check that my second mug will hit the table before your shooter.

Daniel:
I got enough: a deal, it is. Waiter! two mugs and one shooter of beer please!
_________________________

What had to happen happened. Jack took his first mug, drank it slowly,
and carefully put it upside down on the table to trap the shooter.

As soon as Daniel saw the mug rotating, he knew that this one would be difficult to swallow.