And our alternative hypothesis is that the drug just has an effect. We didn't say whether the drug would lower the response time or raise the response time. We just said the drug has an effect that it will not, the mean when you have the drug will not be the same thing as the population mean. And then the null hypothesis is no, your mean with the drug is going to be the same thing as the population mean. It has no effect. In this situation, where we're really just testing to see if it had an effect, whether an extreme positive effect or an extreme negative effect would have both been considered an effect, we did something called a two-tailed test. This is called a two-tailed test.