A study was conducted by Union Carbide to identify the optimal catalyst preparation conditions in the conversion of monoethanolamine (MEA) to ethylenediamine (EDA), a substance used commercially in soaps. The initial experimental plan was chosen to screen four metals (Fe, Co, Ni, and Cu) and four catalyst support classes (low acidity, high acidity, porous, and high surface area).

a. How many metal support combinations are possible for this experiment?
b. All four catalyst supports are tested in random order with one of the metals. How many different orderings of the four supports are possible with each metal?