Rotation diagrams of the N-, O-, and S-bearing species with multiple unblended transitions detection in HC, mm2, mm3a, and mm3b. Panels in row I show two states of HCOOCH₃ lines, with the blue and black dots from observation of ground state (ν = 0) and torsionally excited state (ν = 1) lines, respectively. With the optically thin assumption, fittings for each state are plotted in blue or black, respectively, and fittings for all the transitions are plotted in red. Non-detection of HCOOCH₃ lines are not shown. Panels in rows II–VI show fittings with the optically thin assumption, with 3σ upper limits from non-detections plotted as arrows. Blue dashed lines in row III are fittings with upper limits included. The estimated temperature and total column density from each fitting is indicated in each panel. Errors are derived from scatters in the data points.