Exploring the deep ocean floor: Hot springs and strange creatures. The ocean floor is home to many unique communities of plants and animals. Most of these marine ecosystems are near the water surface, such as the Great Barrier Reef, a 2,000-km-long coral formation off the northeastern coast of Australia.
Quick Answer. Egyptian pyramids often took 10 years or more to complete. According to the Greek historian Herodotus, the Great Pyramid at Giza was built in 20 years by 100,000 workers and was meant to be a tomb for Pharaoh Khufu.
How long did it take to build the Empire State Building? It took 410 days, which is one year and 45 days to build the empire state building. That was over 200,000 hours of labor, during the course of roughly 14 months, to build whatâ¦ was the tallest building at that time. 21 people found this useful.