So let's see what's the most probable situation that we can get. Okay, so what's the likelihood that we're going to get four different molecules all on the left side? Well, this thing could only occur one time, or there's one way that this can occur. So let's look at this side. What's the likelihood that you get two different molecules on the left side of the container or on the left container? Okay, well, there are six different ways that this can occur.