What is steep walled valley created by a river or stream?

What is group efficiency of pile? How did the first nations way of life change when the settlers from France came to the Great Lakes-St Lawrence lowlands? Where does more precipitation occur over the oceans or over the land? Witch sea is Egypt beside? Is there a limit to how deep you can go in the ocean? What famous mounds the archaeologists believe Adena built? What color is the ambassador bridge? What is the process where oceanic crust is sinking under continents at deep ocean trenches? Why was Oceanside picked fr the location of San Luis Rey? How far can the Congo river's currents flow into the Atlantic ocean? What layer of the ocean does the marlin live in? Did slaves build the Washington monument? Why are tiruvanantapuram and shillong in June than in July? What happened in pearl harbour? What are the river deltas in South America? What is the budget of Mackinac Island State Park Commission? What are the ground conditions that may affect the shelter you'll build in the Grand Canyon? What do the azerbaijians call azerbaijan? What country touches pacific Indian and Atlantic oceans? Are rainforest's only found in Brazil?