In 1951, the British Royal Navy ship HMS Challenger II surveyed the Challenger Deep trench of the Pacific Ocean, located between Indonesia and Japan, establishing it as the deepest known point of any ocean on Earth. Less than a decade later, a US Navy deep-sea diving submersible descended to the trench floor. There, the crew observed small sole and flounder and noted that the floor consisted of diatomaceous ooze. What is the maximum depth surveyed at the Challenger Deep? Discuss