So if our null hypothesis is true, the probability of getting a result more extreme than 1.05 seconds, now we are only considering this tail right over here. Let me put it this way. More extreme than 1.05 seconds, or let me say lower, because in the last video we cared about more extreme, because even a really high result would have said, okay, the mean is definitely not 1.2 seconds. But in this case we care about means that are lower. So now we care about the probability of a result lower than 1.05 seconds. That's the same thing as getting a sample from the sampling distribution that's more than three standard deviations below the mean. And in this case we are only going to consider the area in this one tail.