How far from a 7.50 µC point charge will the potential be 210 V? m

At what distance will it be 4.20 ✕ 102 V?

before we can answer, we have to see the choices that are printed there with the question.   that's the only way we can point you to the correct one.

the independent variable, or the one that is intentionally manipulated is the speed.

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force