How can a man go eight days without sleep?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

In a town, there are four houses located at different distances from each other. Following are the distances:

The third house is 60 meters apart from the first house.
The fourth house is 40 meters apart from the second house.
The third house is 10 meters nearer to the fourth house than it is to the second house.

Can you find out the distance between the fourth and the first house?

He digs out tiny caves and stores gold and silver in them. He also built bridges of silver and made crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs his help, yet many people are afraid to let him help them. Who is he?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

What is black when you buy it, red when you use it, and gray when you throw it away?

I’m tall when I’m young, and I’m short when I’m old. What am I?

There was a strange boy who was born before his father. How can this be possible?

Six glasses are in a row. The first three are filled with milk and the last three are empty. By moving only one glass, can you arrange them so that the full and the empty glasses alternate?