What always comes into a house through the keyhole?

Before Balboa discovered the Pacific Ocean, which was the largest ocean before that?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

What does this rebus photo means?

What is the word or phrase below?
R | E | A | D

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

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

our enemy challenges you to play Russian Roulette with a 6-cylinder pistol (meaning it has room for 6 bullets). He puts 2 bullets into the gun in consecutive slots, and leaves the next four slots blank. He spins the barrel and hands you the gun. You point the gun at yourself and pull the trigger. It doesn't go off. Your enemy tells you that you need to pull the trigger one more time, and that you can choose to either spin the barrel at random, or not, before pulling the trigger again. Spinning the barrel will position the barrel in a random position.

Assuming you'd like to live, should you spin the barrel or not before pulling the trigger again?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?