The standard reduction potential for ${\mathrm{Fe}}^{2+}/\mathrm{Fe}\text{ and }{\mathrm{Sn}}^{2+}/\mathrm{Sn}$ electrodes are -0.44 and -0.14 volt respectively. For the given cell reaction ${\mathrm{Fe}}^{2+}+\mathrm{Sn}\to \mathrm{Fe}+{\mathrm{Sn}}^{2+}$, the standard $EMF$ is