JEE Advanced Model Paper 7 with solutions for online practice

2Cu2+ + K4[Fe(CN)6] → one mole of complex (A) and its coordination no. is ‘x’.
Pb2+ + excess of KI → one mole of complex (B) and its coordination no. is ‘y’
Au + NaCN + H2O + O2 → one mole of complex (C) and its coordination no. is ‘z’.
Then ( x + y - z ) is ……….