Imagine you are in a chemistry lab and the teacher is explaining the electrolysis of `CuSO_4` solution and the products liberated after electrolysis. The teacher made two Setups for the electrolysis process. In Set up-I electrolysis of `CuSO_4` solution is done by using Pt electrodes and in Set up-II electrolysis of `CuSO_4` solution is done by using Cu electrodes. Answer the following questions based on this:
(i) In which Set up I or II will the colour of `CuSO_4` solution fades away and why? (ii) Write the chemical reaction taking place at the Cu anode in Set up II.
(iii) Name the product obtained at the anode in Set up I.
iv) Which out of Set up I or II depict refining of crude copper?