Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

You have two rectangular wires.

Both of them have property that when you light the fire from one end , it will take 60 minutes to get completely burn.

However, they do not burn at consistent speed (i.e it might be possible 1st 20% burn in 50 minutes and 80% can burn in 10 minutes).

So how could you measure 45 minutes ?

This is a game of Tic-Tac-Toe which you all might have played innumerable times. Here, we are playing with the black and white markers instead. Also, there is a bit change to the rules. The changed rules allow you to play just three times. After the three markers are put by each of the players, you can only slide your marker into an empty square that shares a common wall with the square that the marker is leaving. You can refer to the figure given. If this is the position of the game, the white's next move would be from 6 to 3. Now, whatever the black one does, the white one will move his marker from 5 to 2 and he will have a three in a row. What you have to decide is if both of the players are using a perfect strategy, will the white player (who plays first) always win? Or it will be the black one who will win always? Or every game will be a draw?

I never was there, I am always to be.
You have never ever seen me, not ever you will.
Yet I am the confidence of everyone.

Who Am I?

There are 100 bulbs in a room. 100 strangers have been accumulated in the adjacent room. The first one goes and lights up every bulb. The second one goes and switches off all the even-numbered bulbs - second, fourth, sixth... and so on. The third one goes and reverses the current position of every third bulb (third, sixth, ninth? and so on.) i.e. if the bulb is lit, he switches it off and if the bulb is off, he switches it on. All the 100 strangers progress similarly.

After the last person has done what he wanted, which bulbs will be lit and which ones will be switched off?

Why is the Hole below a Lock?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

A very interesting trivia question for all.

Why do men's shirts have their buttons on the right side and women's have buttons on the left-hand side?

Before Mount Everest was discovered, what was the highest mountain in the world?