What is the cell potential (standard emf, E°) for the reaction below? \[\frac{x+2}{6}=\frac{y+4}{3}=\frac{z+1}{2}\]and\[{{\cos }^{2}}A+{{\cos }^{2}}C={{\sin }^{2}}B,\] \[\Delta ABC\] \[\left| \begin{matrix} x+y+2z & x & y \\ z & y=z+2x & y \\ z & x & z=x+2y \\ \end{matrix} \right|\]