Consider a conducting sphere with radius $4\mathrm{.}0$ cm$,$ as shown below. A charge of $+7\mathrm{.}0$ microCoulomb is located at B$,$ which is $6\mathrm{.}0$ cm from the left edge of the sphere. A charge of $9\mathrm{.}2$ microCoulomb is added to the sphere at point A$.$ What is the electric force on B$?$ The conducting sphere is replaced with a neutral insulating sphere. Once again, a charge of $9\mathrm{.}2$ microCoulomb is added to the sphere at point A$.$ What is the electric force on B$?$