Which of the following is the most accurate, including the most simplified, form of the equation to assess a change in specific entropy for an ideal gas that is NOT

air and is undergoing an isothermal process? \text { a } \quad s_{2}-s_{1}=\frac{Q}{T_{b}}+\frac{\sigma}{m} \text { b } \quad \mathrm{s}_{2}-\mathrm{s}_{1}=\mathrm{c}_{\mathrm{p}} \ln \left(\frac{\mathrm{T}_{2}}{\mathrm{~T}_{1}}\right)-\operatorname{Rin}\left(\frac{\mathrm{P}_{2}}{\mathrm{P}_{1}}\right) \text { d } \quad s_{2}-s_{1}=-\operatorname{Rin}\left(\frac{P_{2}}{P_{1}}\right) \text { c } \mathrm{S}_{2}-\mathrm{S}_{1}=\operatorname{Rin}\left(\frac{\mathrm{P}_{2}}{\mathrm{P}_{1}}\right) \text { e } \mathrm{s}_{2}-\mathrm{s}_{1}=\operatorname{cin}\left(\frac{\mathrm{T}_{2}}{\mathrm{~T}_{1}}\right) f \quad 5_{2}-s_{1}=0 s_{2}-s_{1}=s_{2}^{0}-s_{1}^{0} h \quad s_{2}-s_{1}=c_{p} \ln \left(\frac{T_{2}}{T_{1}}\right) \text { i } \quad s_{2}-s_{1}=s_{2}^{0}-s_{1}^{0}-\operatorname{Rin}\left(\frac{P_{2}}{P_{1}}\right)