Which is heavier: a ton of bricks or a ton of feathers?

Name a key which is hardest to turn.

What does this rebus means ?

PROG WORKRESS

There is a unique number which when multiplied by any number from 1 to 6, we will get the new number that contains the same digits only.

Can you find that number?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

What is both possible and impossible at the same time?

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 I get the answer 24 by only using the numbers 8,8,3,3?

You can use the main signs add, subtract multiply and divide.

Find the hidden panda in the image below.

What time is it when an elephant sits on a fence?