please don't copy solution from others and explain step by step. thanks in advance

consider the following 4 well-formed formulas ( wfff) (1) Father (Tom, Fifi) (2) Alive (Tom) (3) xy Father (x,y) parent (x,y) (4) xy( parent (x,y) Alive (x)) older (x,y) a) Convert these well-formed formulas (wff) into conjunctive normal form. b) use the resolution refutation algorithms to prove the following: older (Tom, Fifi) =? write each step also write down substation made during unification if any