The standard electrode potentials of some electrodes are :
Electrode `{:("Electrode",Zn^(2+)|Zn ,Cd^(2+)"|Cd",Ag^(+)|Ag,Fe^(2+)"|Fe"),(E^@(V),-0.76,-0.40,0.80V,-0.44V):}`
Which of the following cells are feasible and give their `E^(@)(cell)` ?
(i) `Zn|Zn^(2+)||Cd^(2+)|Cd` (ii) `Fe|Fe^(2+)||Zn^(2+)|Zn`
(iii) `Cd|Cd^(2+)||Ag^(+)|Ag` (iv) `Fe|Fe^(2+)||Ag^(+)|Ag`