Answer: This zone measures 20,000 feet to 36,000 feet below the surface, and has a name that means "unseen."
Step-by-step explanation:
The Had-opelagic zone is the deepest part of the ocean and measures at a depth of 20,000 ft to 36,000 ft below the surface. It is so deep that it has not be explored fully and so got conveniently named ''unseen''.
Most of these zones are in the Pacific ocean and are found in trenches on the ocean floor such as the Mariana Trench. Naturally, due to the pressure at that depth, only a few fish species can survive such as eels and snailfishes.