So for each of those scenarios, four different people could sit in chair two. Now, for each of these scenarios now, so we have 20 scenarios, five times four, we have 20 scenarios where we've seated seat one and seat two. How many people could we now seat in seat three for each of those 20 scenarios? Well, three people haven't sat down yet, so there's three possibilities there. So now there's five times four times three scenarios for seating the first three people. How many people are left for seat four? Well, two people haven't sat down yet, so there's two possibilities.