Difficult Riddles

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?

How can one talk without saying a single word?

If you're 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door?

Keyboard words are not in alphabetical order, Why?

I look at you, you look at me I raise my right, you raise your left. What am I?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

We can be boring,Or interesting.
We can be long,Or short.
We can have pictures,Or just words.
Many love us,But many also hate us.
What are we?