[单选题]
Two charges are sepa 0*fs 4s8+cs0ge1k b d;gitoporated by a v0sr n)u o9:mjaf,gk0o px f+:distance d and exert mutual attractive forces of F on each othe9+x:fj o0)umoa0,krvnfp gs :r. If the charges are separated by a distance of d/3, what are the new mutual forces?
