Consider two Einstein solids with $N_A=3$ and $N_B=6$ in thermal equilibrium. The number of total energy units shared between them is $q=9.$ The equilibrium distribution is between $q_A=1$ and $q_A=4$

a$.$ Find the value of $q_A$ at equilibrium, and calculate its entropy as a multiple of $k_B.$

b$.$ If the energy unit is $lon,$ estimate the temperature at equilibrium as a multiple of $lo\frac{n}{k_B}.$