(a) How many fixed establishment positions were there for the (i) Detectives: Violent Crimes (Group A), (ii) Detectives: Economic Crimes (Group B), (iii) Detectives: General Crimes (Group C) and (iv) Detectives: Service Centre in each police station in each province (aa) in the 2015-16 financial year and (bb) since 1 April 2016, (b) how many of the specified positions were (i) filled and (ii) vacant in each case and (c) on which salary scale is each of the positions?