 library, I guess. Anyways, it takes 9.25 hours to fly 3,925 miles from London to Chicago. What is the average speed of the airplane? So average speed is going to be the distance divided by the time, right? So we have both of those factors given to us. The distance in this case is 3,925 miles, the time, 2,5 hours. So speed and velocity are effectively the same thing. So like we said, velocity is distance divided by time. So we have those. So distance in this case, 3,9. And it doesn't specify what units it wants to do. We'll just keep it in miles per hour. That's cool with me. And I just take one minute divided by 30 sig figs, 4 sig figs, so the answer is going to be 3. Very good. So I got 4,24 miles per hour. So that's the average speed this plane is going to be. Any questions on this? Again, after doing those kinetic energy ones, this one should be probably a breeze, though.