Whale lice that feed of the skin of great whales and other large mammals, often causing scarring to the skin, what type of of interaction is this

The correct answer is parasitism.

Parasitism, in the field of evolutionary biology, refers to an association between species, where the parasite, the organism, lives on or in another species, the host, creating some kind of harm in it, and is amended structurally to this way of life.

The parasites include protozoans, like as the agents of sleeping sickness, malaria, and amoeba dysentery; animals, like lice, hookworms, mosquitoes, and vampire bats; fungi, like the agents of ringworm, honey fungus; and plants, like dodder, mistletoe, and the broomrapes.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.