The Great Barrier Reef is the largest living structure on Earth. Coral reefs consist of huge numbers of individual coral polyps (soft-
bodied, invertebrate animals) that are linked together by tissue. The Great Barrier Reef is an interlinked system of about 3,000 reefs and
900 coral islands divided by narrow passages, located just beneath the surface of the Coral Sea.
*write your answer in km (kilometers)