Final answer:
In STEP 2 of testing the hypothesis, scientists formulate a hypothesis, which is a tentative explanation for an observation or set of observations.
Step-by-step explanation:
In STEP 2 of testing the hypothesis, scientists formulate a hypothesis, which is a tentative explanation for an observation or set of observations. This hypothesis helps put the scientist's understanding of the system being studied into a testable form. For example, if the observation is that plants grow taller when given more water, the hypothesis could be that increased water leads to increased plant growth.