Answer:
Step-by-step explanation:
Seismic is a technique or method , the routine, analysis and activity of seisomograms to detect and locate underground nuclear explosions of a region. Seismic waves are measured by an instrument called seismometers.
Snell's law is the relationship between the angle of incidence and refraction of a wave and indices of the refraction of two media.
Snell's law describe how seismic ray paths bend as they travel from one medium to another. When the waves refracted 90°, it travel faster through the medium.