What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

When can we add 2 to 11 and get 1 as the correct answer?

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

You can see three almost identical images below. Can you spot the odd one out from them?

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?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

Why do you find that most of the buildings are deprived of the 13th floor?

Today, I celebrated my 32nd birthday but I was born in 1972.
How is this possible?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

All of the flowers I have are orchids except two. All of the flowers I have are hibiscuses except two. All of the flowers I have are roses except two.

Can you tell me how many flowers I have?