User:!jim/Sandbox

Failed to parse (Conversion error. Server ("/media/api/rest_") reported: "Cannot get mml. TeX parse error: Undefined control sequence \emph"): {\displaystyle {\frac {DN_{sys}}{Dt}}=\int _{c.v.}^{}{\frac {\partial }{\partial t}}(\rho \eta )dV+\int _{c.s.}^{}\rho \eta {\overrightarrow {V_{b}}}\cdot {\widehat {n}}dA+\int _{c.s.}^{}\rho \eta {\emph {\overrightarrow {V_{r}}}}\cdot {\widehat {n}}dA}