Taq polymerase is an enzyme used in the polymerase chain reaction (pcr) to replicate fragments of dna. a study published in 1976 examined the properties of taq polymerase after the enzyme was isolated from thermus aquaticus, a thermophilic bacterium that lives in the hot springs of yellowstone national park. the graph shows one of the results of the study. which statement about enzyme activity is best supported by this graph?