What is the longest word in the dictionary?

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?

Can you move 2 matchsticks to form four equal sized squares.

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

What does the below image rebus riddle means ?

It is an eleven letter word.
The first, second, third and fourth letters form a banquet's name.
The fifth, sixth and seventh letters form a car's name.
The eighth, ninth, tenth and eleventh letters form a mode of transport.

Can you identify what word it is?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Who can jump higher than a Mountain?

Can you count the number of squares in the given picture?

What is the coolest letter in the alphabet?