If a seismic station is 3200 km from an earthquake epicenter, what is the time needed for an s-wave to travel from the epicenter to the seismic station? (1) 4 min 40 sec (2) 6 min 0 sec (3) 10 min 40 sec (4) 11 min 10 sec

Earthquake mainly occur when there is rock movement along a crack on the crust of the earth. The slippage of the rocks causes shock waves that travel on the earth. A focus is a point on the earth where the actual movement takes place and an epicenter is a point which is directly above the focus. Seismographs are devices that record the earthquakes and do so by showing major waves patterns that is p-waves, s-waves and L-waves. Wave travel time from the epicenter to the seismic station can be estimated fro the travel charts.
In this case if the epicenter is 3200 km from the seismic station then the s-wave will take 11 mins 10 sec.