1) The fingerprints of koalas are so similar to humans that they have been mistaken at crime scenes.

2) The term "bull market" refers to a period of rising stock prices, while a "bear market" refers to a period of falling stock prices.

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

4) The word "piano" contains three vowels: I, A, and O.