Select the given code of reagents for following four step conversion and write you answer as abcd. If reagent is used once then you need not to take it again.    

  
1. Br₂ / CCl₄                       2. Br₂ / hν
3. Br₂ / H₂O                        4. alc. KOH / $∆$
5. O₃ / Zn / H₂O                  6. H₂ / Ni
7. NH₂ – NH₂ / EtONa        8. Zn – Hg / HCl