What was mohorovičić's observation?
seismic waves travelled at constant speeds.
seismic waves penetrated all earth's layers.
seismic waves could not go through the brittle crust.
seismic waves travelled at varying speeds.

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.

image result for describe the various types of gene mutationsghr.nlm.nih.gov

the types of mutations include: missense mutation: this type of mutation is a change in one dna base pair that results in the substitution of one amino acid for another in the protein made by a gene. nonsense mutation: a nonsense mutation is also a change in one dna base pair.

explanation:

no i don't feel that humans have oversubscribed some medications