A basin
A basin
A Valley-------------------------No a valley is not surrounded by higher land, the correct answer is a "basin" or a "depression".
The air is thinner the higher you go.
A hollow or depression in the earth's surface is a basin. A basin is usually shaped like a bowl, with the sides higher than the bottom. Some are filled with water, some are empty.
Air pressure toward regions of lower air pressure
Rivers are always surrounded by higher land.
Yes, exactly.Yes, exactly.Yes, exactly.Yes, exactly.
The higher you go the less effect gravity has on you.
Sinking air would add air to the surface, raising the pressure.
I am sure that if you think about the problems encountered by climbers on Mount Everest you might be able to answer that yourself. Near the Earth's surface.
I am sure that if you think about the problems encountered by climbers on Mount Everest you might be able to answer that yourself. Near the Earth's surface.
A depression in geography refers to a low-lying area surrounded by higher ground, often with reduced drainage and increased sediment accumulation. It can be a natural landform or artificially created for water storage or agricultural purposes.