Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

Identify the hidden meaning behind this picture?

I am quite hot but become too cold if you remove the first two letters. What am I?

What has many teeth, but cannot bite?

Move three sticks of the spiral below to form a square.

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

A donkey is behind another donkey
I'm behind that second donkey
But there is a whole nation behind me

It is a murder you can describe in a word.

Can you find the missing piece of the Porsche?

I am an odd number. Take away a letter and I become even. What number am I?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?