What's the only room from which no one can enter or leave

A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

Which is the rope you never skip with?

In the picture, you can see a chess board. On the top left position, the K marks a knight. Now, can you move the knight in a manner that after 63 moves, the knight has been placed at all the squares exactly once excluding the starting square?

Can you spot the man between the coffee bean in the picture below ?

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

If I put in one bird per cage, I have one bird too many. If I put in two bird per cage, I have one cage too many. How many cages and birds do I have?

Can you find the mistake in the below statement?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day