Two spheres, each of mass $M=2.33 \mathrm{~g}$, are attached by pieces of string of length $L=45.0 \mathrm{~cm}$ to a common point. The strings initially hang straight down, with the spheres just touching one another. An equal amount of charge, $q$, is placed on each sphere. The resulting forces on the spheres cause each string to hang at an angle of $\theta=10.0^{\circ}$ from the vertical. Determine $q,$ the amount of charge on each sphere.