Midterm 2 solutions

Here are solutions to midterm 2. I see that I did not write it in the solutions, but it is helpful for sp2 type integrals to recall that $\langle \psi_{2s} | x |  \psi_{2x} \rangle = 3a$ and also $\langle \psi_{2s} | y |  \psi_{2y} \rangle = 3a$.