Answer:
C)evaporating of water
Explanation:that is because waters physical property is lost after evaporating
Frequency can be found by counting the number of troughs per second in a wave diagram.
Answer:

Explanation:
In this process energy must be conserved. On the initial stage, there will be only gravitational potential energy, while on the final stage there will be only elastic potential energy, so they will be equal. We write this as:

Which is the same as:

So we can obtain our mass from there, and for our values:

F = kq1q2/r^2
<span>q1 is first charge </span>
<span>q2 is second charge </span>
<span>k is 9 E9 </span>
<span>r is distance between them </span>
<span>F = (9E9)(2 E-6)(4 E-6)/2^2 = 0.018 N </span>
<span>A postive answer indicates a repulsive force</span>