Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

A man was convicted of a minor offence in Akbar court. Akbar decided to give him a chance. He asked him to give a statement. If the statement is true, he will be killed by lions and if it is false, he will be killed by trampling of wild elephants.

The convicted person requested help from Birbal and since the crime was not a big one, Birbal decided to help him. Whatever Birbal suggested impressed Kabir and he let the convicted person go.

What did Birbal suggest to the person?

Move three sticks of the spiral below to form a square.

A Detective reviewed the information they had on the case so far.

A lady named 'Caterina' was found shot and they already had a list of suspects - Ankit, Tarun, Harish, Manoj and Manish.
The killer is a fan of challenges him by leaving notes ad various places.
* The first was found in a toilet room.
* The second was found in an art room.
* The third was in a restroom.
* the fourth in an underwater room.
* The fifth at the no-smoking room.

All of the notes read the same thing, 'The clues are where you find the notes.' Yet, nothing was found at any place the notes were.
Detective the genius, immediately solved the case.
Who was the killer?

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?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

What does this simple rebus mean?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?