No one wants to have it, but if one got it, he does not want to lose it. What is It?

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?

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

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

A bomb exploded in a room full of married couples and no one died. How?

Find out the missing number in the picture attached:

I have an eye but still cannot see.

Who am I?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

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

Three people enter a room and have a green or blue hat placed on their heads. They cannot see their own hat but can see the other hats.
The colour of each hat is purely random. They could all be green, blue, or any combination of green and blue.
They need to guess their own hat colour by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $10,000 each, but if anyone guesses incorrectly they all get nothing.
What is the best strategy?