Consider the following relations for emf of an electrochemical cell:
(i) EMF of cell = (Oxidation potential of anode) - (Reduction potential of cathode )
(ii) EMF of cell = (Oxidation potential of anode) + (Reduction potential of cathode )
(iii) EMF of cell = (Reduction potential of anode ) + (Reduction potential of cathode )
(iv) EMF of cell = (Oxidation potential of anode) - (Oxidation potential of cathode)
Which of the above relations are correct?