[" 16.A complex "MA_(3)X_(3)" ,where "A" and "X" are unidentate "],[" ligands may give "]

Square planar complex of the type MAXBL (where A, B, X and L are unidentate ligands) shows following set of isomers

If a complex, Ma_(4)b_(2) (where M is a central atom and a and b are mondentate ligands ) has trigonal prismatic geometry, the total number of possible geometrical isomers would be :