XeF₄, SF₄, SiF₄, B, Br, [Cu(NH₃)₄]²-, [FeCl₄]²-, [CoCl₄]²-, and [PtCl₄]²-. Defining shape on the basis of the location of X & Z atoms, the total number of species having a square planar shape is _____ₐ. 3
b. 4
c. 5
d. 6