Ageology student finds a rock formation composed of sedimentary rock. based on the principle of the student concludes that the layers on the bottom are older than the layers on the top.

ANSWER:

Based on the "principle of Superposition", the geology student can say that the layers on top are "younger" than the layers present below.

EXPLANATION:

The principle of superposition is a basic principle in geology which states that in a "sequence of strata", any stratum is "younger" than the one on which it "rests". Sedimentary rocks are formed by deposition of "one layer on top of another". Therefore, the "layers at the bottom will be older" than the layers of rocks that form above the lower ones.  

Is their a picture that goes along with it? ?

Answer: the dna polymerase checks for errors in dna to prevent replication mistakes.
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