The observation that a mammal and a fish can both have fins is an example of A. analogy

B. parsimony

C. ancestry

D. homology

D. homology

Explanation:

This observation is an example of the term known as homology. This is basically comparing how different species can have the same traits and physical design as each other even though they are completely different. This is due to the two species sharing a specific ancestor. That ancestor's trait is passed down throughout the generations even after the split and ends up in two different species.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

explanation:

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