When monkey rotate the gear, which mark will be hit 1 or 2 ?

You need to remove four matchsticks from the picture below and still need to maintain the following as in the original image.
1. 1st row contains 12 matchsticks
2. 2nd row contains 12 matchsticks
3. 1st column contains 12 matchsticks
4. 2nd column contains 12 matchsticks

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

What is more useful when it is broken?

Spot what is wrong here in below Picture?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

If your uncle’s sister is not your aunt, what relation is she to you?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

Find three numbers such that

* When we multiply three numbers, we will get the prime numbers.
* The difference between the second and the first number is equal to the third and second.