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

2) 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.

3) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

4) The word "banana" contains three vowels: A, A, and A.