What is at the end of a rainbow?

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

Find the 8 in the below-given Image.

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

There are forty elephants and they have forty-fore heads. How can this be possible?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

I have eight fingers and two thumbs but I do not live. What Am I?

What has no start, end, or centre?

Accidentally, two trains are running in the opposite direction and enter a tunnel that is 200 miles long. A supersonic bird that has fled the lab and taken shelter in the tunnel starts flying from one train towards the other at a speed of 1000 mph. As soon as it reaches the second train, he starts flying back to avoid collision and meets the first train again at the other end. The bird keeps flying to and fro till the trains collide with each other.

What is the total distance that the supersonic bird has traveled till the trains collided?