According to piaget, what do adolescents employ during the formal operational stage of development that them reason differently than children in the concrete development stage

The answer is propositional thought. It is because the propositional thought is a way of reasoning in an operational way that has the capacity to assess or evaluate a judgment or prepositions, in which they don't have to rely on circumstances that is happening in real life. With that, it enables them to reason differently than of the children.

The best sociological research method would have to be using experiments although it has some disadvantages as well