1) The word "school" contains two vowels: O and O.

2) The world's largest volcano, Mauna Loa in Hawaii, is also one of the most active.

3) 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.

4) The concept of compound interest can be attributed to the ancient Babylonians, who used it in their banking practices.