7. The is a collection of buried, long-dead organisms and can tell us information about prior ancestors - the a fossil is, the it is in age and the related it is to modern organisms.

Fossil.

Explanation:

Fossil is a collection of buried, long-dead organisms that can tell us information about ancestors of an organism. The physical features of fossil provides information about its relationship with modern organisms. The fossil which is present in very deep in the soil are more older than the fossil that is present in less depth. We can find age of the fossil by using radiometric dating methods which tells us about the existence of fossil on the earth.

"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:

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