Name this compound according to iupac nomenclature rules?

Ok so co(g) is not pronoused that. the only clue is that youpronouse it the oppisote way. 

Answer trigonal pyramidal;

Bromine has atomic number  35  which means there are  35 protons  and  44  neutrons to give a total of 79 nucleons. the fact that it's a positive ion means that it has lost an electron; so there'll be  34 electrons. 

No one can answer this im sorry