What does this rebus mean?

O
N
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TIME

Women do it once a year after they turn 19 but men get to do it only once in a lifetime. What is it?

Two trains start at the same time, one from Bangalore to Mysore and the other from Mysore to Bangalore. if they arrive at their destinations one hour and four hours respectively after passing one another, how much faster is one train running than the other?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

Solve the counting riddle by identifying the number of triangles in the given picture.

What does the below image rebus riddle means ?

Which five letter word can be added at the end of below word to form a
valid word?

> Pin
> Check
> Boiling
> View

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?