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 ()

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?

Rumel, A detective who was mere days from cracking an international smuggling ring has suddenly gone missing. While inspecting his last-known location, you find a note:

710 57735 34 5508 51 7718

Currently, there are 3 suspects: Bill, John, and Todd. Can you break the detective's code and find the criminal's name?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

I know a nine-letter word having only one vowel.
Do you ?

Can it be possible to build a house that has all its four walls facing towards the South?

What is black when you buy it, red when you use it, and gray when you throw it away?

What does below rebus means ?

I have no life, but I can die. What am I?

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