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

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

What is the word or phrase?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

John leaves home and then he takes three right turns. John wants to return to home but he was scared of Jacob, who is wearing a mask.

What is John Situation ?

What do you answer even though it never asks you questions?

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

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 ?

The captain of a ship was telling this interesting story: "We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly." How can that be possible?