1) The concept of gravity was famously described by Sir Isaac Newton after an apple fell on his head.

2) The word "triangle" contains four vowels: I, A, E, and E.

3) The shortest scheduled commercial flight lasts just 1.7 miles and connects two Scottish islands, Westray and Papa Westray.

4) The world's oldest tree is believed to be a bristlecone pine named "Methuselah" in California, estimated to be over 4,800 years old.