1) The word "yesterday" contains three vowels: E, A, and A.

2) The world's largest flower is the Rafflesia arnoldii, which can grow up to 3 feet (1 meter) in diameter and weighs about 15 pounds (7 kilograms).

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

4) Kim Kardashian West is an American media personality, businesswoman, and socialite. She gained fame through reality television show "Keeping Up with the Kardashians" and has built a successful brand empire encompassing fashion, beauty, and other ventures.