Final answer:
The nurse is using the scientific method to solve the problem in her care of the client with hypothermia.
Step-by-step explanation:
The nurse is using the scientific method to solve the problem in her care of the client with hypothermia. The scientific method involves making observations, forming a hypothesis, conducting further assessments and gathering data to confirm or refute the hypothesis. In this case, the nurse observed symptoms of hypothermia and conducted a further assessment to confirm the diagnosis by measuring the client's heart rate and core internal temperature.