1) The sunflower is not a single flower but a cluster of small flowers arranged in a spiral pattern.

2) The Yangtze River, also known as the Changjiang River, is the longest river in Asia and the third-longest in the world, stretching over 6,300 kilometers (3,915 miles). It holds immense cultural, historical, and ecological significance for China and the surrounding regions.

3) The sitcom "Friends" is known for its iconic Central Perk coffee shop, where the main characters often gather.

4) The world's largest volcano, Mauna Loa in Hawaii, is also one of the most active. It stands over 13,000 feet (4,000 meters) above sea level.