In some experiment first arbitrary choice is made out of four possibilities, and then arbitrary choice is made out of remaining three possibilities. One way to explain this is with a product of two sample spaces {a, b, c, d}:
omega = {a, b, c, d} × {a, b, c, d}.
a. Develop a 4×4 table in which you write the probabilities of the outcomes.
b. Explain the event "c is one of the chosen possibilities" and determine its probability.