During which month do people sleep the least?

I am white when I am dirty, and black when I am clean. What am I?

A sundial has the fewest moving parts of any timepiece. Which has the most?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

You have a square. What you have to do is cut and reassemble the square such that you create a Red Cross sign that has the same volume as that of the square.

What is common among 11, 69, and 88?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

You’re out on the water and see a boat filled with people. You look away for a second and look back again, but this time you don’t see a single person on the boat. Why? Hint: The boat did not sink.

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.