Topic Details (Notes format)

Which empire was led by Genghis Khan and his successors, spanning much of Asia and Eastern Europe?

Who discovered Cepheid variable stars?

Which wave type requires a medium to travel: light or sound?

Which element has the chemical symbol "Rn"?

Which is the hardest substance in the human body?

Who discovered the buoyancy principle?

Which fiber crop is known for making linen from its stalks?

Who discovered the ancient city of Ur?

Who discovered the tomb of Qin Shi Huang?

Which cat species cannot retract its claws fully and is known for running speed?