When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

Can you make the below equation true by using any three numbers from "1, 3, 5, 7, 9, 11, 13 and 15"?

( ) + ( ) + ( ) = 30

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

What jumps when it walks and sits when it stands?

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

There is something which you can be arrested for attempting but not for successfully completing.

You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

There is a unique number which when multiplied by any number from 1 to 6, we will get the new number that contains the same digits only.

Can you find that number?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?