LVG results produced by the RADEX code for the observed intensity ratios in the EHV, IHV, and SHV ranges (left, middle, and right panels, respectively). The results are shown as T vs. n and n × T (thermal pressure) vs. T plots (lower and upper panels, respectively). The CO (2–1)/(12–11) ratio is indicated in green and the CO (2–1)/(13–12) ratio in blue. The observed ratio is drawn with solid lines, while the line ratio uncertainty (including statistical and 20% of the calibration errors) with dashed lines. N = 2 × 10¹⁷, 5 × 10¹⁷, and 7 × 10¹⁷ cm^-3; and Δν = 40, 50, and 30 km s^-1, for EHV, IHV, and SHV, respectively.