Well, it's one less than our sample size, so our degrees of freedom right over here is equal to four. And so we're ready to use a t-table. So this is a truncated t-table that I could fit on my screen here. And so there's a couple of ways to think about it. Here they actually give us the confidence level, and the reason why that corresponds to a tail probability of.025 is if you take the middle 95% of a distribution, you're going to have 2.5% on either end. That's going to be your tail probability. So that's all that's going on over there.