Panels a–c: depth-dependence of (mean intensity at λ = 2000 Å) for each of the five models (STD, tm30T40, tm30T43, tm30T45, tm30T50); the local Planck function (B_ν: dashed line) is also depicted for comparison. Panels d–f and g–i: runs of (ratio of NLTE to LTE line opacity; ≃ b₁) and S_L ∕B (ratio of line source function to Planck function; ≃ b₂∕b₁) of the Li I 6708 line, respectively. The abscissa for each panel is the logarithm of continuum optical depth at 5000 Å.