The probability that our random variable, the number of cars that pass in an hour, is equal to a particular number, you know, it's equal to 7 cars pass in an hour, is equal to the limit as n approaches infinity of n choose k times, well, we said it was lambda over n to the k successes, times 1 minus lambda over n to the n minus k failures. And we just showed that this is equal to lambda to the kth power over k factorial times e to the minus lambda. And that's pretty neat, because when you just see it in kind of a vacuum, if you have no context for it, you wouldn't guess that this is in any way related to the binomial theorem. I mean, it's got an e in there. It's got a factorial, but you know, a lot of things have factorials in life, so not clear that that would make it a binomial theorem. But this is just the limit as you take smaller and smaller and smaller intervals, and the probability of success in each interval becomes smaller. But as you take the limit, you end up with e. And if you think about it, it makes sense, because one of our derivations of e actually came out of compound interest, and we kind of did something similar there.