Suppose a recording station was located 500 km from the epicenter. What will be the time difference between the first P-wave an the first S-wave

The first supersonic flight was 1947. it was just above the speed of sound. which altitude would you expect captain yeager to have used for his flight? a) sea level b) 1000m c) 13,700m (within altitude used by commercial planes today) d) 85,000m (where meteor showers originate) will mark brainlist