The ratio of Coulomb's electrostatic force to the gravitational force between an electron and a proton separated by some distance is 2.4 $\times 1039. The ratio of the proportionality constant, K = {1 \over {4\pi {\varepsilon _0}}} to the gravitational constant G is nearly (Given that the charge of the proton and electron each = 1.6 \times 10-19 C, the mass of the electron = 9.11 \times 10-31 kg, the mass of the proton = 1.67 \times 10-$27 kg) :