1) The name "Bluetooth" comes from the 10th-century Danish king, Harald Bluetooth, who united Denmark and Norway.

2) The first car with air conditioning was released in 1939.

3) Antarctica is the coldest, driest, and windiest continent on Earth. It is also the highest, with an average elevation of about 7,545 feet (2,300 meters).

4) The Great Barrier Reef in Australia is the largest living structure on Earth and can be seen from space.