Answer:
Seismic waves traveled at varying speeds.
Explanation:
The Moho Discontinuity was discovered by one Croatian seismologist, Andrija Mohorovicic. He realized that the speed of a seismic wave depends on the density of the material the wave is moving through. Mohorovicic interpreted the acceleration of seismic waves observed within the Earth's crust as a change in composition of matter within the Earth.
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