I have teeth but i don't bite. Who Am I ?

What makes this number unique: 8,549,176,320?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

Six people park their car in an underground parking of a store. The store has six floors in all. Each one of them goes to a different floor. Simon stays in the lift for the longest. Sia gets out before Peter but after Tracy. The first one to get out is Harold. Debra leaves after Tracy who gets out on the third floor.

Can you find out who leaves the lift on which floor?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

I am 5 letters long.
My first two tell you who I am
My first 3 could be a medicine
My last three reversed could be a young boy.
My 4th, 3rd and 2nd in that order could be a fruit drink.
If you have me you may hang me round your neck
WHAT AM I ?

Before reading ahead, you must know the fact that only one of the people here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?