Mutations that occur without a known cause are known as:
a. spontaneous mutations
b. induced mutations
c. harmful mutations
d. adaptive mutations
e. reversion mutations

a. spontaneous mutations

Explanation:

Spontaneous mutations occur randomly in all cells and without any agents. Induced mutations are the result of some exposure to a physical or chemical agent called a mutagen. Mutations can be classified as harmful and adaptive regardless of whether they were spontaneous or induced mutations. The reversal mutation is when a given mutation is reversed by another mutation so that the nucleotide is changed back to its original state.

"a scientist studying a whale and its surroundings would need to understand the structure of atoms in case something was negatively affecting the whale or its surroundings."

explanation:

this was from the link provided:

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.