B.absorb neutrons to prevent chain reactions which become uncontrollable
Option A 3......
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To solve this problem it is necessary to apply the concepts related to the Moment. The moment in terms of the Force and the time can be expressed as

F = Force

At the same time the moment can be expressed in terms of mass and velocity, mathematically it can be given as

Where
m = Mass
Change in velocity
Our values are given as

By equating the two equations we can find the Force,



Therefore, the net average force will be:

The negative symbol indicates that the direction of the force is upwards.
Answer:
D. The net electrical charge of the Earth.
Explanation:
All the other three choices affect the gravitational force. I remember from middle school.
You should write meter per second square for the acceleration in words