How do sand dunes move?
use the terms leeward and windward in your explanation.

As the sand mound grows, the point of maximum sand deposition on the leeward face moves closer to the summit, causing a steepening of the leeward face relative to the windward face. The steepening and growing dune now forces wind out over the top of the dune rather than down the leeward face.

answer

i think the answer is a) as air pressure in an area increases, the density of the gas particles in that area decreases.

hope it

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