"The proton and neutron have nothing to do with the isotope little billy"
PRETTY SURE ITS A AND C BUT I LOOKED IT UP AND IM ALMOST POSITIVE THARS IT
The answer is that it is constant. The relation between electric field and electric potential is given as, E= -gradient (V). The E, the partial rate of change of Electric potential, in the equation implies that the V, the partial differential of the potential of the three-dimensional space (assuming it is considered) is constant.
The Soviet Union's Sputnik 1, it was launched October 4th 1957.
