Observe the three circles you have drawn. Where is the earthquake's epicenter?
I drew 3 circles and at the place were it creates a border, this border is the earthquake's epicenter. Here the epicenter is on the border of Kentucky.
Wich city on the map is closest the earthquake's epicenter? How far is the city from the epicenter, in kilometers?
 The closest city is chicago and it is about 600 km away from the earthquake's epicenter
In which of the three cities listed on the data table would seismographs detect the Earthquake first? Last?
I think that the closest cities to the epicenter would feel it first and the farthest last. So first Chicago, then Houston and finally Salt lake city.
 How far from San Francisco is the epicenter you found? What would be the difference in arrival times of the P waves and S waves for a recording station in San Francisco?
It would take it about 4:40 to arrive at san francisco.
What happens in arrival times between P waves and S waves as the distance from the earthquake increases?
P waves and S waves have more chances of meeting and the force of the earthquake has diminished a lot.
Review the procedure you follwed in this lab and then answer the following question. When you are trying to locate an epicenter, why is it necessary to know the distance from the epicenter for at least three recording stations?
The more recording stations (or circles) we have the more precise we can be. I there are like 10 points we would probably only have something like 2mm in comun, so we could be precise. But if we only had 1 recording station the epicenter could be anywhere inside the center.