1) The oldest known musical instrument is a flute made from a bird bone, estimated to be around 43,000 years old.

2) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

3) The Cricket World Cup is held every four years and features teams from around the world competing for the prestigious title.

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