(a) (10 points) Draw an energy level diagram for the electronic structure of hydrogen and lithium atoms for energy levels up to n=3. Label the energy axis in terms of effective nuclear charge. Explain the difference between the energy diagrams.

(b) (10 points) Draw a rough sketch of the radial probability distribution for the state n=2, l=1 for lithium and hydrogen atoms. (Label your x axis with a sensible unit, but you can leave all tick marks blank). Explain your reasoning.