The speed of propagation of seismic waves is about 4km/s an earthquake takes place in Turkey at 13:21:00 the center of the earthquake is at 500km from beirut at waht time would a seismograph in beiurt rcord the earthquake?​

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.