In class we derived the expression for density of states, Z(E), in 3D for a particle in a box of side a and isotropic mass m. The result is shown in equation 6.5. i) Derive the expression for density of states for a particle in a 2D box (or square) of side a and isotropic mass m. ii) Derive the expression for density of states for a particle in a 2D box (or square) of side a and anisotropic mass, say, m x and m y where m x m y . Note that E=Ex Ey where Ex (Ey ) is a function of nx (ny ) and m x (m y )