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. Afterward, what is the charge of sphere A?

Ahole in the ground in the shape of an inverted cone is 14 meters deep and has radius at the top of 11 meters. the cone is filled to the top with sawdust. the density of the sawdust depends upon the depth, x, following the formula ρ ( x ) = 2.5 + 1.2 e − 0.7 x kg/m3. find the total mass of sawdust in the conical hole.