(Solved): The figure shows four identical conducting spheres that are actually well separated from one an ...

The figure shows four identical conducting spheres that are actually well separated from one another. Sphere W (with an initial charge of zero) is touched to sphere $A$ and then they are separated. Next, sphere $W$ is touched to sphere $B$ (with an initial charge of $?34e$ ) and then they are separated. Finally, sphere $W$ is touched to sphere $C$ (with an initial charge of 52e), and then they are separated. The final charge on sphere $W$ is $16e$. What multiple of e gives the initial charge on sphere $A$ ?