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Equate the gravitational force to the electrostatic force:
<span>KC²/D² = Gm²/D² → C = m√[G/K] = 7.6√[6.67E-11/9E9] = 6.54E-10 coulombs </span>
<span>Number of electrons N = 6.24E18*C = 4.083E9 electrons</span>
Longer than visable light
I had to look for the options and here is my answer:
The two requirements for nuclear fusion that are needed to be met in order for the elements hydrogen and helium fuse to make heavier elements are extremely high temperatures and density. Hope this helps.