The time-resolved spectra in different models and for different viewing angles. The solid lines are spectra near the beginning of T₉₀ (t_obs = t_5%), and the dashed lines show the spectra near the end of T₉₀ (t_obs = t_95%). Colors represent different models, as in Figure 5. The black dashed line on the upper panel is the Planck function with kT = 0.8keV. All spectra are quasi-thermal and only slightly broader than the Planck function.