Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

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?

In which direction should the missing arrow point?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

If a wheel has 54 spokes, how many spaces are there between the spokes?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

Can you solve this picture maths equation?

A quarter is one-fourth of a dollar but Mr. John has changed the equation as below :

DOLLAR * 4 = QUARTER

Can you replace each letter with a digit to make the above solution correct?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.