A sphere of radius G contains uniform negative charge density p per unit volume. The total charge of this spherical cloud is -2e, which is the charge of the two electrons in the molecule. Embedded in this negative cloud are two point charges, each of charge +e, representing the two hydrogen nuclei (protons). Suppose that the protons are symmetrically located at a distance b from the center, as shown in the figure. Also, suppose that the positive charges do not disturb the uniformity of the negative charge distribution. (a) [2] Find p in terms of e and the other quantities given in the problem. (b) [3] Find the force (magnitude and direction) that the negative cloud exerts on each proton. As always, express your answer in terms of quantities given in the problem. (c) [3] Find the force (magnitude and direction) that one proton exerts on the other. (d) [2] Find the ratio b/a for which the protons feel no net force. \f