Answer:
Chemical and Biological weathering.
Explanation:
Processes that break down and weaken earth minerals are known as weathering. Over time, this can lead to erosion, in which huge sections of rock and stone are carried away, changing landscapes. Physical weathering alters the material structure of rocks, while chemical weathering alters their chemical structure.
Answer:

Explanation:
Given that

As both charges are negative so there exist force of repulsion in direction as shown in figure.

Angle at which force F12 is acting is



Force exerted on charge -2e is equal in magnitude to F12 but is in opposite direction


The first human made object made to orbit earth was the Soviet Union's Sputnik 1, it launched the 4th of October 1957.
I'm going to assume this is over a horizontal distance. You know from Newton's Laws that F=ma --> a = F/m. You also know from your equations of linear motion that v^2=v0^2+2ad. Combining these two equations gives you v^2=v0^2+2(F/m)d. We can plug in the given values to get v^2=0^2+2(20/3)0.25. Solving for v we get v=1.82 m/s!