What are the materials called through which waves pass energy?
a. waves
b. amplitudes
c. mediums

C. mediums

Waves cannot transfer energy through other waves and amplitudes are only the equilibrium point of the wave so it's not able to transfer energy since technically it is also a wave but just a point on it.  

Competition. interaction among organisms that compete for the same natural resource (food, shelter, water, space) in an ecosystem. predation. an interaction in which one organism kills another for food. predator. prey. symbiosis. mutualisum. commensalisum. parasitisum.

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