Use dimensional analysis to show that the wavelength scale of blackbody radiation is given by th

Use dimensional analysis to show that the wavelength scale of blackbody radiation is given by λ_th = hc/k_BT . The average radiation energy in a cavity depends only on its volume and not on its shape when λ_th ≪ L, , where L is a typical length scale characterizing the cavity. How low must the temperature be for the shape to matter if L ≈ 1 cm?