nebular gas within the 5-level atom approximation. The O$^{+}$ (low ionization) zone electron temperature can be related to the O$^{++}$ (high ionization) zone electron temperature [e.g., @campbell86; @pagel92]. We used the relation between $t_{2}$ and $t_{3}$ proposed by @pagel92, based on the photoionization modeling of @stasinska90 to determine the low ionization zone temperature: $${t_{2}}^{-1} = 0.5({t_{3}}^{-1} + 0.8).$$ The low and high ionization region temperatures are tabulated in Table \[tbl4\]. Typically regions are assumed to have electron temperatures within the range of 1 to 2 $\times10^4$ K. Temperatures for the present sample agree with this approximation, spanning 10,800 K - 15,200 K for the low ionization region, and 9,600 K - 19,400 K in the high ionization region.

Since the MMT spectra include emission lines from both O$^+$ and O$^{++}$, we determine oxygen abundances based on our estimated two zone electron temperatures. Spectra which contained measurable \[\] $\lambda\lambda$6717,6731 were used to determine electron densities consistent with the low density limit. Thus, it is reasonable to simply assume $n_{\rm e}=10^2$ cm$^{-3}$ for this sample. Ionic abundances were calculated with: $${\frac{N(X^{i})}{N(H^{+})}\ } = {\frac{I_{\lambda(i)}}{I_{H\beta}}\ } {\frac{j_{H\beta}}{j_{\lambda(i)}}\ }.
    \label{eq:Nfrac}$$ The emissivity coefficients, which are functions of both temperature and density, were determined using 