Earthquakes are essentially sound waves—called seismic waves—traveling through the earth. Because the earth is solid, it can support both longitudinal and transverse seismic waves. The speed of longitudinal waves, called P waves, is 8000 m/s. Transverse waves, called S waves, travel at a slower 4500 m/s. A seismograph records the two waves from a distant earthquake. The S wave arrives 2.0 min after the P wave. Assume that the waves travel in straight lines, although actual seismic waves follow more complex routes. If the S wave arrives 2.3 min after the P wave, how far away was the earthquake?