Physics: Charge and Coloumb’s Law, physics homework help

Two identical metal spheres A and B are in contact. Both are initially neutral. 1.0×1012 electrons are added to sphere A, then the two spheres are separated.

a) Afterward, what is the charge of sphere A? Express your answer to two significant figures and include the appropriate units.

b) Afterward, what is the charge of sphere B? 
Express your answer to two significant figures and include the appropriate units.