wrote her letters in a colloquial style / the broken syntax and casual enunciation of conversational English Similar: informal (used of spoken and written language)
Best Answer: The mid-oceanic ridge can be described as the longest mountain range. It includes the Mid-Atlantic ridge, and all other such ridges. They form a complete system that is 65000 km long. The Mariana's Trench is the deepest. It's 11.03 kilometres deep. I don't know how you define underwater mountain.
If you measured the mountain that is tallest from its base and included mountains that have a base underwater, then Mauna Kea in Hawaii would be the tallest. It is a volcano that has risen 33,464 ft/10,200 m/6.3 miles above the sea floor.