And so this is really a combinations problem. This is really equivalent to saying how many ways are there to choose two people from a pool of four, or four choose two, or four choose two. And so this is going to be, well, how many ways are there to permute four people into three spots, which is going to be four times three, which we just figured out right over there, which is 12. Actually, why don't I do it in that green color so you see where that came from. So four times three, and then you're going to divide that by the number of ways you can arrange two people. Well, you can arrange two people in two different ways. One's on the left, one's on the right, or the other one's on the left, and the other one's on the right.