1) In Chinese mythology, the Dragon Boat Festival (also known as Duanwu Festival) is celebrated to honor Qu Yuan, a poet and statesman of ancient China. It involves dragon boat races, eating sticky rice dumplings (zongzi), and performing rituals to ward off evil spirits and protect against diseases.

2) The concept of separation of powers, as articulated by French philosopher Montesquieu, refers to the division of government responsibilities into distinct branches, such as the executive, legislative, and judicial, to prevent concentration of power.

3) The Dow Jones Industrial Average (DJIA) is a stock market index that tracks the performance of 30 large, publicly owned companies in the United States.

4) The first modern Olympic marathon race was held at the 1896 Olympics in Athens and has since become one of the most iconic and challenging events in athletics.