It would most likely be the last one. Erosion is effectively the process of natural forces breaking down rock or soil, which allows it to move from place to place with the aid of forces like wind or water. I would say the answer would be the first one, but it only says rock, while erosion can affect more than just rocks. Hope this helps.
Answer:

Explanation:
Given:

Required:
Coordinates of the Midpoint of HX
Solution:
Midpoint (M) of HX, for
is given as
.
Let 

Thus:

Convert to improper fractions





Answer:
There is no such thing as "earthquake weather". ... Very large low-pressure changes associated with major storm systems (typhoons, hurricanes, etc) are known to trigger episodes of fault slip (slow earthquakes) in the Earth's crust and may also play a role in triggering some damaging earthquakes.
Explanation:
hope i helped