How many times in a given day, minutes and hour clock comes in a straight line ?

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?

Find the missing letter in the last circle logically in the given below picture.

What goes up but never comes down?

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

What part of the chicken has the most feathers?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

A man was just doing his job when his suit was torn. Why did he die three minutes later?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?