1) The smallest unit of time is known as a zeptosecond, which is equal to one trillionth of one billionth of a second.

2) Elvis Presley, often referred to as the "King of Rock and Roll," has sold over one billion records worldwide.

3) Michael Jackson's album "Thriller" is the best-selling album of all time, with estimated sales of over 66 million copies worldwide.

4) In Aztec mythology, Quetzalcoatl is a prominent deity often depicted as a feathered serpent. He is associated with creation, fertility, and wind, and is considered a cultural hero and patron of priests and rulers. The arrival of Spanish conquistadors was interpreted by some as the return of Quetzalcoatl.