Read the passage given below and then answer the questions given below the passage. Some words may be highlighted for your attention. Read carefully.

Icebergs are pieces of ice that formed on land and float in an ocean or lake. Icebergs come in all shapes and sizes, from ice-cube-sized chunks to ice islands the size of a small country. The term "iceberg" refers to chunks of ice larger than 5 meters (16 feet) across. Smaller icebergs, known as bergy bits and growlers, can be especially dangerous for ships because they are harder to spot. The North Atlantic and the cold waters surrounding Antarctica are home to most of the icebergs on Earth. Icebergs form when chunks of ice calve, or break off, from glaciers, ice shelves, or a larger iceberg. Icebergs travel with ocean currents, sometimes smashing up against the shore or getting caught in shallow waters.

When an iceberg reaches warm waters, the new climate attacks it from all sides. On the iceberg surface, warm air melts snow and ice into pools called melt ponds that can trickle through the iceberg and widen cracks. At the same time, warm water laps at the iceberg edges, melting the ice and causing chunks of ice to break off. On the underside, warmer waters melt the iceberg from the bottom up. Icebergs pose a danger to ships traversing the North Atlantic and the waters around Antarctica. After the Titanic sank near Newfoundland in 1912, the United States and twelve other countries formed the International Ice Patrol to warn ships of icebergs in the North Atlantic. The International Ice Patrol uses airplanes and radars to track icebergs that float into major shipping lanes. The U.S. National Ice Center uses satellite data to monitor icebergs near Antarctica. However, it only tracks icebergs larger than 500 square meters (5,400 square feet). Icebergs can also serve as tools for scientists, who study them to learn more about climate and ocean processes.