Well depending on the speed of both of those things is were the rock will be placed and it also determines how fast can an environment change
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Sorry I'm so late, but I just took this test and the answer is white (for people who didn't study well ;) )
Answer:

Explanation:
According to the free-body diagram of the system, we have:

So, we can solve for T from (1):

Replacing (3) in (2):

The electric force (
) is given by the Coulomb's law. Recall that the charge q is the same in both spheres:

According to pythagoras theorem, the distance of separation (r) of the spheres are given by:

Finally, we replace (5) in (4) and solving for q:

I believe the answer is Nonmaterial Culture.