Can you find out which number multiplied by itself will give the output as 12345678987654321?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

In the picture given below, can you find out which digit will take place of the question mark?

Rebus Puzzle Definition: A rebus is an illusion device that uses pictures to represent words or parts of words.
What does This Rebus Puzzle Identify?

Get total of 120 by using five zeros 0,0,0,0,0 and any one mathematical operator.
Do you ?

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Decode this picture on T-Shirt and tell what it says ?

Can you place three balls such that the equation shown in the picture holds true?

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?