Four couples have these standard potentials: Al³⁺/Al is -1.66 V, Pb²⁺/Pb is -0.13 V, Cu²⁺/Cu is…

Four couples have these standard potentials: $\text{Al}^{3+}/\text{Al}$ is $-1.66\ \text{V}$, $\text{Pb}^{2+}/\text{Pb}$ is $-0.13\ \text{V}$, $\text{Cu}^{2+}/\text{Cu}$ is $+0.34\ \text{V}$ and $\text{Cl}_2/\text{Cl}^-$ is $+1.36\ \text{V}$. Any two can be joined to make a cell. Find the largest and the smallest cell potential.