When I get multiplied by any number, the sum of the figures in the product is always me. 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?

What has one letter and starts with an E?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Usually, a boxing match consists of twelve rounds. In a particular friendly match between two heavyweights, the match was finished in the ninth round itself as one of the boxers knocked out the other one.

But, in that fight, no man threw even a single punch.

How can this be possible?

Replace the question mark with the correct number in below Picture:

What runs around the whole yard without moving?

The answer I give is yes, but what I mean is no. What was the question?

Steffi's daughter Jazelle needs to be picked up from school every day.
Steffi asks one of her colleagues to pick up Jazelle from the school. Steffi devised a password system to confirm that Jazelle goes with the correct colleague only.

The password on Monday was SJM16.
The password on Wednesday was TAW39.

What will the password be for Friday?

How many sides does a circle have?