An external force that is being applied in the direction of the displacement
C. Populations.
Hope that's right.
To solve this problem we will apply the concepts related to the work theorem for which it is defined as the product of Force and distance. In turn, we will use the energy conservation theorem for which the applied work must be equivalent to the total kinetic energy on the body.
The work is defined as

Here,
F = Force
d = Displacement
Replacing with our values we have that


Now by conservation of energy,



Solving for v,


Therefore the correct answer is D.
Explanation:
In geology, there are 5 divisions of time on the time scale. They are:
- eons
- eras
- periods
- epochs
- ages
Eons are the largest time period, while ages are the shortest time period. The rest of the above listed are in between the two.