You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?

Using the clues below, what four numbers am I thinking of?

The sum of all the numbers is 31.
One number is odd.
The highest number minus the lowest number is 7.
If you subtract the middle two numbers, it equals two.
There are no duplicate numbers.

I have teeth but i don't bite. Who Am I ?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

Find the combined weight of the Cat, Dog and Rabbit in the given picture.

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

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

The centre of the third figure is empty. What digit should fit inside?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?