1) The Amazon rainforest produces more than 20% of the world's oxygen.

2) The concept of quantum computing explores the use of quantum mechanics principles to perform complex computations, potentially revolutionizing fields such as cryptography and optimization.

3) In Norse mythology, Ragnarok is a cataclysmic event that signifies the end of the world. It involves a series of apocalyptic battles and natural disasters, leading to the destruction of the gods and the world as it is known. From the ashes, a new world and a new generation of gods emerge.

4) The longest-running TV show in history is "The Simpsons," which has been on the air since 1989 and has over 700 episodes.