Answer:
- mountainside: temperature extremes have more influence
- beach: wind and waves have more influence
Explanation:
It depends on what you mean by "factors that control weathering" and where the beach and mountain are located.
If we assume that the rock on the mountain is at a place that has seasonal snow, and the beach is in a temperate climate, then we can make these observations.
The rock on the mountainside will be "weathered" by freezing and thawing, and by plant growth (roots). These will tend to enlarge any cracks in the rock, breaking it apart. While the mountainside may be windy, that wind may not carry particles that would tend to erode the rock surface.
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The rock on a beach will be most affected by wave and water action, tending to smooth any exposed surface. Freezing and thawing action is less common, due to the moderating influence of the water on the local weather. In some cases, plant growth may also be a factor. Wind may pick up beach sand, further tending to smooth any exposed surfaces.
