The second one, we're asking about a trait of a bunch of people. And there's variability in that trait. They're not all the same age. And so we'll need statistics to come up with some features of the data set to be able to make some conclusions. We might say, on average, the people who have watched this video in 2013 are 18 years old, or 22 years old, or the median is 24 years old, whatever it might be. Do dogs run faster than cats? So once again, there are many dogs and many cats.