Metal sphere \(\mathrm{A}\) is hung from the ceiling by a long, thin string and given a positive charge. An identical sphere B is suspended nearby with an identical string and given a negative charge that has the same magnitude as the charge on \(\mathrm{A}\). The two spheres are \(50 \mathrm{~mm}\) apart when in equilibrium. If an identical sphere \(C\) carrying no surplus charge is placed between them, does the distance between A and B increase, decrease, or remain the same?