If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?

What does below chemistry rebus means?

I’m tall when I’m young, and I’m short when I’m old. What am I?

When it's bad luck to meet a black cat?

Take one out and scratch my head, I am now black but once was red. What am I?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

Forwards I am heavy, backward I am not. What am I?

A man is trapped in a room. The room has only two possible exits doors. Through the first door there is a room constructed from magnifying glass. The blazing hot sun instantly fries anything or anyone that enters. Through the second door there is a fire-breathing dragon. How does the man escape?

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?