I am a prime number.
The double of myself is equal to the square of me.

which number am I?

Without looking at a calendar, within a minute name, a boy's name using 5 consecutive 1st letters of 5 consecutive months

During which month do people sleep the least?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

You stand in front of two doors. A guard stands next to each door. You know the following things: one path leads to paradise, the other leads to death. You cannot distinguish between the two doors. You also know that one of the two guards always tells the truth and the other always lies. You have permission to ask one guard one question to discover which door leads to paradise. What one question would you ask to guarantee you enter the door to paradise?

A woman shoots her husband.

Then she holds him under water for over 5 minutes.

Finally, she hangs him.

But 5 minutes later they both go out together and enjoy a wonderful dinner together.

How can this be?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

Be active and find the killer in the picture Riddle below.

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?