In electromagnetic waves, energy is transferred through vibrations of electric and magnetic fields. In sound waves, energy is transferred through vibration of air particles or particles of a solid through which the sound travels.
Benthos are "organisms inhabiting the seafloor" according to one source, so I would say the answer is C.
Answer:
There are 4 tryptophans in the protein.
Explanation:
According to question, protein contains one tyrosine residue and say x number of tryptophans.
Concentration of protein solution = 1.0 micromolar = 
Molar absorptivity of a protein solution : 


Length of the cuvette = l = 1.0 cm
Absorbance of protein solution at 280 nm = A = 0.024
( Beer-Lambert's law)

Solving for x :
x = 4
There are 4 tryptophans in the protein.
Heart: Pumps blood through the body
Bone: Provides structure
Stomach: Breaks down food into small particles
Lungs: Oxygenates blood