(b) With reference to the molecule of sulfur tetrafluoride (SF): (1) Determine the oxidation number of each element. [1 mark] (ii) Draw and justify its Lewis structure. [3 marks) (ii) Calculate the formal charge for each atom. [1 mark] (iv) Use the VSEPR model to predict the molecular geometry, the F-S-F angles and the polarity of the molecule. Justify your statements. [6 marks]