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?
I sometimes come in a can but I'm not food.
I sometimes come in a bottle but I'm not a beverage.
I come in different colors but I'm not a rainbow.
I'm sometimes used with canvas but I'm not a tent.
I'm used with a brush but I'm not toothpaste.
What Am I?
We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly. How can that be possible?
The sailors had their backs against either ends of the ship.